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/* GchemIB Bright Study Edition — clean, vivid, print-ready */
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/* Detailed topic lessons and written-response practice */
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/* Scope and sequence roadmap */
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@media(max-width:900px){.sequence-terms{grid-template-columns:1fr}}
@media print{.sequence-term{break-inside:avoid}.sequence-note{background:#fff!important}}

/* Visual chemistry field-guide notes */
.topic-hero{display:grid;grid-template-columns:minmax(0,1.35fr) minmax(180px,.65fr);gap:22px;align-items:center;padding:26px 28px;margin:12px 0 18px;border:1px solid #dce6fb;border-radius:20px;background:radial-gradient(circle at 82% 18%,rgba(19,168,158,.14),transparent 32%),linear-gradient(135deg,#f5f7ff 0%,#effaf8 100%);overflow:hidden}.topic-hero-copy h2{font-size:clamp(25px,3vw,36px);line-height:1.15;letter-spacing:-.7px;margin:10px 0 12px;color:#202e4a}.topic-hero-label{font-size:10px;letter-spacing:1.5px;font-weight:850;color:#5369c8}.topic-hero .note-intro{max-width:650px;font-size:15px;line-height:1.75;color:#52617b;margin:0}.topic-hero-pills{display:flex;flex-wrap:wrap;gap:7px;margin-top:17px}.topic-hero-pills span{font-size:11px;font-weight:750;padding:6px 10px;border:1px solid #dce4f8;background:rgba(255,255,255,.75);border-radius:999px;color:#4659a7}.topic-hero-art{display:flex;flex-direction:column;align-items:center;justify-content:center;min-height:145px;padding:12px;border-radius:15px;background:rgba(255,255,255,.68);border:1px solid rgba(211,223,244,.9);color:#6177cb}.topic-art{display:block;width:100%;max-width:245px;height:auto;overflow:visible}.topic-hero-art>span{font-size:11px;font-weight:750;letter-spacing:.3px;color:#64718b;margin-top:3px}.topic-video-card{display:flex;align-items:center;gap:15px;padding:16px 18px;margin:18px 0 23px;border:1px solid #e0e6f1;border-radius:15px;background:#fff;box-shadow:0 6px 20px rgba(35,52,83,.045)}.video-icon{display:grid;place-items:center;flex:0 0 42px;width:42px;height:42px;border-radius:13px;background:#fff0f0;color:#e04444;font-size:17px}.topic-video-copy{flex:1;min-width:0}.topic-video-copy strong{font-size:14px;color:#283651}.topic-video-copy p{font-size:12px;line-height:1.55;color:#68758d;margin:4px 0 0}.topic-video-link{flex-shrink:0;text-decoration:none;white-space:nowrap}.note-learning{padding:19px 21px;border-radius:15px;background:#f7f8ff;border:1px solid #e5e8fb;margin:18px 0 22px}.note-learning h3{display:flex;align-items:center;gap:9px;margin:0 0 12px}.learning-spark{display:inline-grid;place-items:center;width:25px;height:25px;border-radius:8px;background:#e6eaff;color:#4f62ca}.note-learning ul{display:grid;grid-template-columns:1fr 1fr;gap:10px 22px;margin:0;padding-left:20px}.note-learning li{font-size:13px;line-height:1.6;padding-left:2px;color:#4f5d75}.visual-note-section{position:relative;margin:15px 0;padding:20px 22px;border:1px solid #e4e9f3;border-radius:16px;background:#fff;box-shadow:0 5px 18px rgba(33,49,78,.035);overflow:hidden}.visual-note-section:before{content:"";position:absolute;left:0;top:0;bottom:0;width:4px;background:linear-gradient(180deg,#6178e8,#26b7a5)}.note-section-top{display:flex;align-items:center;gap:10px;margin-bottom:10px}.visual-note-section .note-section-number{display:inline-grid;place-items:center;width:32px;height:32px;border-radius:10px;background:#edf0ff;color:#4e61c9;font-weight:850;font-size:12px}.note-section-label{font-size:9px;letter-spacing:1.2px;font-weight:850;color:#8a94a8}.visual-note-section h3{font-size:18px;line-height:1.35;margin:0 0 9px;color:#273651}.visual-note-section p{font-size:14px;line-height:1.8;color:#53617a;margin:0}.section-takeaway{display:flex;align-items:center;gap:10px;margin-top:14px;padding-top:11px;border-top:1px dashed #e1e7f0}.section-takeaway span{font-size:9px;letter-spacing:.9px;font-weight:850;color:#14998e;white-space:nowrap}.section-takeaway strong{font-size:11px;color:#63708a;font-weight:650}.note-callout,.example-box{border-radius:15px;padding:19px 21px;margin:17px 0}.note-callout{border:1px solid #f1dfb3;background:linear-gradient(135deg,#fff9e9,#fffdf7)}.example-box{border:1px solid #cfece6;background:linear-gradient(135deg,#effbf8,#f9fffd)}.note-callout>strong,.example-box>strong{display:block;font-size:10px;letter-spacing:1.1px;margin-bottom:7px}.note-callout>strong{color:#a36b12}.example-box>strong{color:#148d80}.note-callout p,.example-box p{font-size:14px;line-height:1.75;margin:0;color:#495873}
@media(max-width:700px){.topic-hero{grid-template-columns:1fr;padding:21px}.topic-hero-art{min-height:110px}.topic-hero-art .topic-art{max-width:210px}.topic-video-card{align-items:flex-start;flex-wrap:wrap}.topic-video-copy{flex-basis:calc(100% - 60px)}.topic-video-link{margin-left:57px}.note-learning ul{grid-template-columns:1fr}.visual-note-section{padding:17px 17px}.section-takeaway{align-items:flex-start;flex-direction:column;gap:4px}}
@media print{.topic-video-card,.note-actions,.screen-only{display:none!important}.topic-hero,.visual-note-section,.note-learning,.note-callout,.example-box{break-inside:avoid;box-shadow:none}.topic-hero{background:#f5f7ff!important}}

/* GchemIB Aurora palette + interactive learning cards */
:root{--bg:#f3f6fb;--panel:#ffffff;--panel2:#f8faff;--line:#dce5f2;--text:#17243b;--muted:#65748d;--teal:#0d9488;--blue:#5267d8;--purple:#8b5cf6;--amber:#e6a23c;--radius:18px;--shadow:0 14px 36px rgba(34,53,91,.09)}
body{background:radial-gradient(ellipse at 8% 0%,#e3f7f4 0,transparent 32%),radial-gradient(ellipse at 95% 8%,#eee9ff 0,transparent 29%),var(--bg);color:var(--text)}
.sidebar{background:#18243c;border-right-color:#263653}.brand-copy strong{color:#fff}.brand-copy small{color:#a9b8d2}.sidebar-label,.section-kicker{color:#94a6c4}.nav-link{color:#c1cce0}.nav-link:hover{background:#263654;color:#fff}.nav-link.active{background:linear-gradient(100deg,#234d62,#303b68);border-color:#42677c;color:#fff}.nav-count{background:#2a3a59;color:#d4e4f4}.mini-card{background:linear-gradient(145deg,#243e55,#282e50);border-color:#40526f}.topic-hero{background:linear-gradient(125deg,#e5f8f5,#f0efff 58%,#fff5e6)!important;border-color:#d8e6f3!important}.topic-hero h2,.topic-hero-copy{color:#1c2a45}.topic-hero-label{color:#0f827c}.topic-hero-pills span{background:#fff;color:#344461;border:1px solid #dce5f2}.topic-video-card,.note-learning,.visual-note-section,.topic-test-question,.formula-card,.panel,.stat-card{background:rgba(255,255,255,.94);border-color:#dce5f2;box-shadow:0 8px 24px rgba(34,53,91,.045)}.topic-video-copy strong,.visual-note-section h3{color:#202e49}.topic-video-copy p,.visual-note-section p,.note-learning li{color:#5b6982}.note-learning{background:linear-gradient(135deg,#f0f5ff,#f0fbf8)}.learning-spark{background:#dfe8ff;color:#4b5ed0}.visual-note-section:before{background:linear-gradient(180deg,#6578e8,#17aa9a)}.visual-note-section .note-section-number{background:#e7edff;color:#4f61c8}.note-callout{background:linear-gradient(135deg,#fff7e7,#fffdf8);border-color:#f1dfb3}.example-box{background:linear-gradient(135deg,#e8fbf6,#f8fffd);border-color:#c8eee4}.btn-primary{background:linear-gradient(120deg,#0f9488,#5267d8);border-color:transparent;color:#fff}.btn-primary:hover{filter:brightness(1.04)}
.interactive-section{padding:0}.interactive-section summary{list-style:none;display:flex;align-items:center;gap:12px;padding:19px 21px;cursor:pointer}.interactive-section summary::-webkit-details-marker{display:none}.section-summary-copy{display:grid;gap:4px;flex:1}.section-summary-copy strong{font-size:17px;line-height:1.35;color:#202e49}.section-toggle{display:grid;place-items:center;width:29px;height:29px;border-radius:9px;background:#e8edff;color:#4f61c8;font-size:20px;flex-shrink:0}.interactive-section[open] .section-toggle{transform:rotate(45deg);background:#ddf7f0;color:#0b877e}.section-content{padding:0 22px 20px 65px}.section-content p{margin:0}.interactive-section summary:focus-visible{outline:2px solid var(--teal);outline-offset:-4px;border-radius:14px}
@media(max-width:700px){.interactive-section summary{padding:16px}.section-content{padding:0 17px 18px 17px}.section-summary-copy strong{font-size:15px}}

/* Break lesson explanations into readable, numbered concept bites */
.concept-bites{display:grid;gap:9px;list-style:none;padding:0;margin:0}.concept-bites li{display:grid;grid-template-columns:28px minmax(0,1fr);align-items:start;gap:10px;padding:11px 13px;border:1px solid #e5ebf5;border-radius:12px;background:linear-gradient(100deg,#f8faff,#fff);color:#4e5d76;font-size:13px;line-height:1.7}.bite-dot{display:grid;place-items:center;width:25px;height:25px;border-radius:8px;background:#e4f6f2;color:#11877f;font-size:10px;font-weight:850}.section-content>p{margin:0}.topic-hero .note-intro{max-width:68ch}
@media(max-width:700px){.concept-bites li{font-size:12px;padding:10px;gap:8px}}

/* ─────────────────────────────────────────────────────────────
   GchemIB design refresh — balanced editorial study workspace
   ───────────────────────────────────────────────────────────── */
:root{--bg:#f5f6f8;--panel:#fff;--panel2:#f8fafc;--line:#e3e7ee;--text:#20283a;--muted:#697386;--teal:#167c75;--blue:#4866bd;--purple:#7861b0;--amber:#c58a35;--radius:16px;--shadow:0 8px 26px rgba(31,43,66,.055)}
html{scroll-behavior:smooth}body{background:#f5f6f8;color:#20283a;font-family:"DM Sans",Inter,system-ui,sans-serif;font-size:14px;line-height:1.6}button,input,select,textarea{font:inherit}button,a,input,select,textarea{transition:background-color .18s ease,border-color .18s ease,box-shadow .18s ease,transform .18s ease}
.app-shell{min-height:100vh}.sidebar{width:252px;background:#202a40;border:0;padding:27px 17px 20px;box-shadow:5px 0 24px rgba(29,40,62,.04)}.brand{padding:0 9px 30px}.brand-mark{border-radius:12px;background:#d7eee7;color:#244a49;box-shadow:none}.brand-copy strong{font-size:19px;color:#fff;letter-spacing:-.5px}.brand-copy small{color:#aebbd0;font-size:8px;letter-spacing:1.25px}.sidebar-label{color:#9aa8bf;font-size:9px;letter-spacing:1.5px;padding:0 12px 12px}.side-nav{gap:4px}.nav-link{padding:11px 12px;border-radius:10px;color:#c0c9d8;font-size:12px;font-weight:600}.nav-link:hover{background:#2b3852;color:#fff}.nav-link.active{background:#e1f1ed;border:1px solid #e1f1ed;color:#205d57}.nav-link.active .nav-icon{color:#247b72}.nav-icon{font-size:15px;color:#b2bfd1}.nav-count{background:#d0e8e1;color:#28685f}.mini-card{background:#293750;border:1px solid #3c4b65;border-radius:13px;padding:16px}.mini-card-icon{color:#b8e3d8}.mini-card strong{color:#fff}.mini-card p{color:#b9c5d7}.text-button{color:#c9eee5}.sidebar-foot{color:#aebbd0}
.main-area{margin-left:252px;min-width:0}.topbar{height:70px;padding:0 clamp(20px,3.3vw,48px);background:rgba(255,255,255,.9);border-bottom:1px solid #e6e9ef;backdrop-filter:blur(14px)}.breadcrumbs{font-size:12px;color:#858ea0}.breadcrumbs strong{color:#263148}.global-search{background:#f5f7fa;border:1px solid #e5e9f0;border-radius:10px}.global-search:focus-within,.search-field:focus-within{border-color:#94c9bd;box-shadow:0 0 0 3px #dff1ec}.global-search input{color:#29344b}.icon-button{background:#fff;border:1px solid #e3e7ee;color:#526076;border-radius:10px}.avatar{background:#e3f1ed;color:#2c6961}
.content-wrap{max-width:1480px;padding:30px clamp(20px,3.3vw,48px) 28px;margin:0 auto}.page{animation:pageIn .28s ease both}@keyframes pageIn{from{opacity:.65;transform:translateY(4px)}to{opacity:1;transform:translateY(0)}}
.hero{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(300px,.95fr);align-items:center;gap:clamp(22px,4vw,58px);padding:clamp(28px,4vw,52px);min-height:360px;border:1px solid #e2e7ee;border-radius:22px;background:linear-gradient(112deg,#fff 0%,#fff 53%,#f0f6f4 100%);box-shadow:0 10px 35px rgba(34,50,76,.045);overflow:hidden}.hero h1{font-size:clamp(34px,4vw,54px);line-height:1.08;letter-spacing:-2.2px;color:#202a40;margin:18px 0 15px}.hero h1 span{color:#267c72}.hero-copy>p{max-width:450px;color:#6a7486;font-size:14px;line-height:1.8}.eyebrow{color:#66768b;font-size:9px;letter-spacing:1.55px}.eyebrow-dot{background:#3a9c8b;box-shadow:0 0 0 4px #e3f4ee}.hero-actions{gap:10px;margin-top:23px}.btn{min-height:40px;border-radius:10px;padding:10px 15px;font-size:12px;font-weight:700;box-shadow:none}.btn-primary{background:#277e73;border:1px solid #277e73;color:#fff}.btn-primary:hover{background:#206c63;transform:translateY(-1px);box-shadow:0 6px 14px #277e7322}.btn-secondary{background:#fff;border:1px solid #dfe5ed;color:#3c4960}.btn-secondary:hover,.btn-ghost:hover{background:#f0f5f4;border-color:#cbded8}.btn-ghost{background:transparent;border:1px solid #e1e6ed;color:#48566d}.hero-proof{color:#758096;font-size:11px}.proof-avatars i{background:#e0f0eb;border-color:#fff;color:#276c63}.hero-visual{min-height:280px;border:1px solid #e1ebe7;border-radius:18px;background:radial-gradient(circle at 48% 45%,#e1f3ee 0,transparent 45%),linear-gradient(145deg,#f8fbfa,#edf3f4);overflow:hidden}.hero-visual .orb{opacity:.65}.molecule{max-width:100%;filter:saturate(.75)}.visual-caption{background:#fff;border:1px solid #e2e8ec;border-radius:12px;box-shadow:0 5px 18px #20344a0c;color:#28344b}.visual-caption small{color:#778194}.floating-chip{background:#fff;border:1px solid #e3e8ed;box-shadow:0 5px 18px #24374c0c;color:#44536a;border-radius:9px;font-size:10px}
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.page-intro{display:flex;align-items:center;justify-content:space-between;gap:22px;margin:3px 0 25px}.page-intro h1{font-size:clamp(28px,3vw,36px);line-height:1.2;letter-spacing:-1.2px;color:#202a40;margin:7px 0 9px}.page-intro p{color:#6e798d;font-size:12px;line-height:1.8;max-width:690px;margin:0}.intro-stat{min-width:110px;padding:15px 19px;border:1px solid #e2e8ed;border-radius:14px;background:#fff;text-align:center}.intro-stat strong{font-size:27px;line-height:1.2;color:#287d70;letter-spacing:-1px}.intro-stat span{display:block;color:#7b8698;font-size:10px;margin-top:4px}
.toolbar{display:flex;gap:11px;margin-bottom:18px}.search-field{min-height:43px;border:1px solid #e1e6ee;border-radius:11px;background:#fff}.search-field input,.toolbar select{color:#354158}.toolbar select{border:1px solid #e1e6ee;border-radius:11px;background:#fff;padding:0 13px;min-height:43px}
.notes-layout{display:grid;grid-template-columns:minmax(220px,270px) minmax(0,1fr);gap:20px;align-items:start}.topic-list{position:sticky;top:88px;max-height:calc(100vh - 112px);overflow:auto;padding:8px;border:1px solid #e3e7ee;border-radius:15px;background:#fff;box-shadow:0 5px 20px rgba(32,47,70,.025)}.topic-list button,.topic-item{border-radius:9px}.topic-list button:hover,.topic-item:hover{background:#f3f7f6}.topic-list button.active,.topic-item.active{background:#e4f2ee;color:#235f58;border-color:#cfe5de}.note-reader{min-width:0;border:1px solid #e3e7ee;border-radius:17px;background:#fff;padding:clamp(16px,2.1vw,28px);box-shadow:0 6px 24px rgba(32,47,70,.03)}.note-actions{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:17px}.topic-hero{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(190px,.75fr);gap:20px;align-items:center;padding:26px;border:1px solid #dceae5;border-radius:17px;background:linear-gradient(120deg,#f3faf7,#f3f5fc)!important;box-shadow:none}.topic-hero h2{font-size:clamp(23px,2.4vw,31px);line-height:1.2;letter-spacing:-.9px;color:#243148;margin:10px 0}.topic-hero .note-intro{font-size:12px;line-height:1.8;color:#68768b}.topic-hero-label{font-size:9px;letter-spacing:1.3px;color:#337f73}.topic-hero-pills{display:flex;flex-wrap:wrap;gap:7px;margin-top:15px}.topic-hero-pills span{font-size:9px;padding:5px 9px;border:1px solid #e0e9e6;border-radius:99px;background:#fff;color:#526579}.topic-hero-art{display:grid;justify-items:center;align-content:center;min-width:0;padding:12px}.topic-hero-art .topic-art{width:min(100%,220px);max-height:170px}.topic-hero-art>span{font-size:9px;color:#81908f;margin-top:5px}.note-meta{display:flex;flex-wrap:wrap;gap:8px;margin:15px 0 18px}.note-meta span{padding:5px 9px;border-radius:7px;background:#f4f6f8;color:#778295;font-size:8px;letter-spacing:.7px}.topic-video-card{display:grid;grid-template-columns:40px minmax(0,1fr) auto;align-items:center;gap:13px;margin:17px 0;padding:14px 16px;border:1px solid #e3e8ef;border-radius:13px;background:#fff;box-shadow:none}.video-icon{width:38px;height:38px;border-radius:11px;background:#fcebea;color:#c95a53}.topic-video-copy strong{font-size:12px;color:#2b374d}.topic-video-copy p{font-size:10px;line-height:1.55;color:#7b8698;margin:3px 0 0}.topic-video-link{font-size:10px;white-space:nowrap}.note-learning{margin:16px 0;padding:17px 19px;border:1px solid #e1e9f3;border-radius:13px;background:#f7f9fd;box-shadow:none}.note-learning h3{font-size:14px;color:#29364b}.note-learning ul{gap:8px 18px}.note-learning li{font-size:11px;line-height:1.65;color:#647187}
.visual-note-section{margin:10px 0;border:1px solid #e4e8ef;border-radius:13px;background:#fff;box-shadow:none;overflow:hidden}.visual-note-section:before{width:3px;background:#82bcb0}.interactive-section summary{padding:16px 17px}.note-section-number{width:30px;height:30px;border-radius:9px;background:#edf4f2;color:#32786f;font-size:10px}.section-summary-copy{gap:3px}.note-section-label{font-size:8px;letter-spacing:1px;color:#8893a4}.section-summary-copy strong{font-size:14px;color:#2c374c}.section-toggle{width:27px;height:27px;background:#f0f3f7;color:#617086;font-size:17px}.section-content{padding:0 18px 18px 61px}.concept-bites{gap:7px}.concept-bites li{grid-template-columns:24px minmax(0,1fr);gap:9px;padding:10px 12px;border:1px solid #edf0f4;border-radius:10px;background:#fafbfc;color:#58657a;font-size:11px;line-height:1.75}.bite-dot{width:23px;height:23px;background:#e5f3ef;color:#327a70;font-size:9px}.section-takeaway{gap:9px;margin-top:12px;padding-top:10px;border-top:1px solid #edf0f4}.section-takeaway span{font-size:8px;color:#2d8a7c}.section-takeaway strong{font-size:10px;color:#647187}.note-callout,.example-box{padding:17px 19px;border-radius:13px;box-shadow:none}.note-callout{background:#fff9ee;border-color:#f0e2c6}.example-box{background:#f0f8f5;border-color:#d8eae4}.note-callout>strong,.example-box>strong{font-size:9px;letter-spacing:1px}.note-callout p,.example-box p{font-size:12px;line-height:1.8;color:#566278}
.topic-test{margin-top:25px;padding-top:22px;border-top:1px solid #e7ebf1}.test-heading h3{font-size:20px;color:#27344a;margin:7px 0}.test-heading p{font-size:12px;color:#778297}.topic-test-question{padding:16px;margin:12px 0;border:1px solid #e3e8ef;border-radius:12px;background:#fff}.test-question-meta{display:flex;flex-wrap:wrap;justify-content:space-between;gap:8px;font-size:8px;color:#7c8799;letter-spacing:.7px}.topic-test-question h4{font-size:12px;line-height:1.7;color:#303d52;margin:10px 0}.written-answer,textarea,input,select{color:#29354b}.written-answer{width:100%;border:1px solid #dfe5ed;border-radius:10px;background:#fafbfd;padding:11px;font-size:12px}.written-answer:focus{border-color:#9bcbbf;box-shadow:0 0 0 3px #e3f3ee}.answer-hint{font-size:10px;color:#7b8698}.model-answer{padding:17px;border-radius:12px;background:#f4f8f6;border:1px solid #dceae5;color:#536278}.model-answer li{margin:7px 0;font-size:12px;line-height:1.8}.topic-test-actions{display:flex;flex-wrap:wrap;gap:9px}.note-footer{margin-top:23px;padding-top:15px;border-top:1px solid #e8ecf1;font-size:9px;color:#8a94a4}
.formula-grid{gap:14px}.formula-card{border:1px solid #e3e8ef;border-radius:14px;background:#fff;box-shadow:none}.formula-card:hover{border-color:#c5ded6;box-shadow:0 8px 22px #233c4d0b}.sequence-terms{gap:17px}.sequence-term{border:1px solid #e2e7ee;border-radius:15px;background:#fff;overflow:hidden;box-shadow:none}.sequence-term-head{background:#f5f8f7;border-bottom:1px solid #e6ebe9}.sequence-term-head h2{color:#2b374c}.sequence-table th{background:#fafbfc;color:#7b8697}.sequence-table td{color:#556177;border-color:#edf0f4}.sequence-note{border:1px solid #eadfca;background:#fff9ee;border-radius:12px;color:#665b48}.periodic-wrap{border:1px solid #e1e7ee;border-radius:15px;background:#fff;padding:14px;overflow:auto}.periodic-grid .element{border-radius:7px;border:1px solid #e4e9ef}.element-detail{border:1px solid #e1e7ee;border-radius:14px;background:#fff}.practice-layout,.tool-grid,.tutor-layout{gap:16px}.practice-main,.practice-side,.calculator-card,.tutor-chat,.tutor-guide,.privacy-note{border:1px solid #e3e7ee;border-radius:15px;background:#fff;box-shadow:none}.quiz-top{color:#718096}.quiz-progress-track{height:5px}.quiz-question h2,.quiz-question h3{color:#29364b}.quiz-option{border:1px solid #e2e7ee;border-radius:10px;background:#fff;color:#4e5c72}.quiz-option:hover{background:#f2f8f6;border-color:#bcdcd2}.quiz-option.selected,.quiz-option.correct{background:#e9f5f0;border-color:#9acbbb;color:#245f56}.quiz-option.incorrect{background:#fff1ef;border-color:#efc4bd;color:#9b4840}.result-box{border:1px solid #dce9e4;border-radius:10px;background:#f5faf8;color:#2f6259}.calculator-card label{color:#657187}.calculator-card input,.chat-compose textarea{border:1px solid #dfe5ed;border-radius:10px;background:#fafbfd}.tool-title h3{color:#29354b}.tutor-chat{overflow:hidden}.chat-header{border-bottom:1px solid #e8ecf1}.chat-messages{background:#fafbfd}.message.assistant .message-body{background:#fff;border:1px solid #e3e8ef;color:#4c5a70}.message-body strong{color:#2c384e}.suggestion-chips button{border:1px solid #dfe8e4;background:#f3f8f6;color:#35746b;border-radius:8px}.chat-compose{background:#fff;border-top:1px solid #e7ebf1}.send-button{background:#277e73;color:#fff;border-radius:10px}.chat-disclaimer{color:#8a94a4}.site-footer{border-top:1px solid #e2e7ee;color:#818b9b}.site-footer a{color:#287d70}
.toast{background:#202a40;color:#fff;box-shadow:0 8px 24px #202a4022}
@media(max-width:1150px){.feature-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.hero{gap:22px;padding:28px}.notes-layout{grid-template-columns:220px minmax(0,1fr)}}
@media(max-width:850px){.sidebar{width:245px;transform:translateX(-100%);transition:transform .22s ease}.sidebar.open{transform:translateX(0)}.main-area{margin-left:0}.content-wrap{padding:22px 18px}.topbar{padding:0 18px}.hero{grid-template-columns:1fr}.hero-visual{min-height:245px}.notes-layout{grid-template-columns:1fr}.topic-list{position:relative;top:auto;max-height:270px}.topic-hero{grid-template-columns:1fr}.topic-hero-art{display:none}.page-intro{align-items:flex-start}.lower-grid{grid-template-columns:1fr}}
@media(max-width:560px){.topbar{height:62px}.breadcrumbs{display:none}.top-actions{margin-left:auto}.global-search{max-width:175px}.content-wrap{padding:17px 12px}.hero{padding:23px 19px;min-height:0}.hero h1{font-size:37px;letter-spacing:-1.5px}.hero-visual{min-height:210px}.feature-grid{grid-template-columns:1fr 1fr;gap:9px}.feature-card{padding:14px}.feature-card p{font-size:10px}.card-bottom{font-size:9px}.page-intro{flex-direction:column}.intro-stat{display:flex;align-items:center;gap:10px;padding:10px 14px}.intro-stat strong{font-size:22px}.toolbar{flex-direction:column}.toolbar select{width:100%}.topic-video-card{grid-template-columns:36px minmax(0,1fr)}.topic-video-link{grid-column:2;justify-self:start}.note-learning ul{grid-template-columns:1fr}.section-content{padding:0 13px 14px}.interactive-section summary{padding:13px}.section-summary-copy strong{font-size:12px}.concept-bites li{font-size:10px;padding:9px}.topic-test-actions .btn{width:100%}.site-footer{flex-wrap:wrap;gap:9px}.site-footer>span:nth-child(2){width:100%;order:3}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;scroll-behavior:auto!important;transition:none!important}}
@media print{body{background:#fff}.sidebar,.topbar,.note-actions,.topic-video-card,.screen-only{display:none!important}.main-area{margin:0}.content-wrap{padding:0}.note-reader,.visual-note-section,.topic-test-question{box-shadow:none;break-inside:avoid}.interactive-section:not([open])>.section-content{display:block}.hero{box-shadow:none}}


/* VISUAL STUDY NOTES — cards, diagrams, short chunks, no text walls */
.visual-map-card{margin:18px 0 22px;background:linear-gradient(135deg,#f7fafc,#f0f7f5);border:1px solid #dce6e9;border-radius:18px;padding:19px 20px 15px;color:#243746;overflow:hidden}
.visual-map-heading{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin-bottom:8px}
.visual-map-heading span{font-size:9px;letter-spacing:1.5px;font-weight:800;color:#287c72;background:#dff1ec;padding:6px 9px;border-radius:7px}
.visual-map-heading strong{font:800 13px Manrope,sans-serif;letter-spacing:.2px}
.topic-diagram{display:block;width:100%;height:auto;max-height:190px;overflow:visible}
.visual-map-caption{font-size:11px;color:#647787;padding-top:7px;border-top:1px solid #dfe8eb}
.topic-key-chips{display:flex;gap:7px;flex-wrap:wrap;margin:15px 0 5px}
.topic-key-chip{font-size:11px;font-weight:700;color:#2a665f;background:#e3f2ed;border:1px solid #cde7df;border-radius:8px;padding:6px 9px}
.topic-hero-pills{display:flex;gap:7px;flex-wrap:wrap}
.topic-hero-pills span{font-size:9px;letter-spacing:.5px;font-weight:800;padding:6px 8px;border-radius:7px;background:#edf2f8;color:#52677a}
.note-learning{padding:18px!important}
.learning-route{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px;margin-top:14px}
.learning-route>div{display:grid;grid-template-columns:27px 1fr;column-gap:8px;align-items:center;padding:11px;background:#f4f7fa;border:1px solid #e2e9ee;border-radius:12px}
.learning-route>div>span{grid-row:span 2;display:grid;place-items:center;width:27px;height:27px;border-radius:9px;background:#dff1ec;color:#267a70;font-size:12px;font-weight:800}
.learning-route strong{font-size:10px;letter-spacing:.7px;color:#2b4054}
.learning-route small{font-size:10px;color:#758697;line-height:1.3}
.note-section-list{margin:20px 0}
.notes-list-heading{margin-bottom:12px}
.notes-list-heading h3{font:800 21px Manrope,sans-serif;margin:5px 0;color:var(--text)}
.notes-list-heading p{margin:0;color:var(--muted);font-size:12px}
.visual-note-section{border:1px solid var(--line);background:var(--panel);border-radius:14px;margin:9px 0;overflow:hidden}
.visual-note-section summary{list-style:none;display:flex;align-items:center;gap:12px;padding:15px;cursor:pointer}
.visual-note-section summary::-webkit-details-marker{display:none}
.visual-note-section summary:hover{background:#f1f6f7}
.visual-note-section .note-section-number{display:grid;place-items:center;flex:0 0 36px;height:36px;border-radius:11px;background:#e4f2ee;color:#287c72;font:800 12px Manrope}
.section-summary-copy{display:grid;gap:3px;flex:1;min-width:0}
.visual-note-section .note-section-label{font-size:8px;letter-spacing:1.3px;font-weight:800;color:#6b8a93}
.visual-note-section summary strong{font:750 14px Manrope,sans-serif;color:#243746}
.section-toggle{display:grid;place-items:center;width:26px;height:26px;border-radius:50%;background:#edf2f5;color:#3d6d71;font-size:18px;transition:transform .18s}
.visual-note-section[open] .section-toggle{transform:rotate(45deg)}
.visual-note-section .section-content{padding:0 15px 15px 63px}
.concept-bites{display:grid;gap:8px;margin:0;padding:0}
.concept-bite{display:grid;grid-template-columns:25px minmax(0,1fr);gap:9px;align-items:start;padding:10px 11px;background:#f6f8fa;border:1px solid #e8edf0;border-radius:10px;color:#354a5d;font-size:12px;line-height:1.55}
.bite-dot{display:grid;place-items:center;width:23px;height:23px;background:#e0eeeb;color:#287c72;border-radius:7px;font-size:9px;font-weight:800}
.section-takeaway{display:flex;align-items:center;gap:9px;flex-wrap:wrap;margin-top:11px;padding:9px 11px;border-left:3px solid #66b3a4;background:#eaf5f1;border-radius:0 8px 8px 0}
.section-takeaway span{font-size:8px;letter-spacing:1.2px;font-weight:800;color:#287c72}
.section-takeaway strong{font-size:11px;color:#315b59}
.visual-callout{display:flex;align-items:flex-start;gap:12px;margin:15px 0;padding:16px;border:1px solid #ead8ae;border-radius:14px;background:#fff8e9;color:#574728}
.callout-icon{display:grid;place-items:center;flex:0 0 30px;height:30px;border-radius:9px;background:#f3e0b5;font-weight:900;color:#875c16}
.visual-callout>div:last-child{min-width:0}
.visual-callout strong{font-size:10px;letter-spacing:1.1px}
.callout-bites{display:grid;gap:7px;margin-top:8px}
.callout-bite{font-size:12px;line-height:1.5;padding:8px 10px;background:#fffdf8;border-radius:8px}
.visual-example{padding:16px;border:1px solid #dce6f0;border-radius:14px;background:#f1f6fc;color:#2b4156}
.example-heading{display:flex;align-items:center;gap:10px;margin-bottom:12px}
.example-heading>span{display:grid;place-items:center;width:32px;height:32px;border-radius:10px;background:#dce8fb;color:#476cb7;font-size:18px}
.example-heading>div{display:grid;gap:2px}
.example-heading strong{font-size:10px;letter-spacing:.9px}
.example-heading small{font-size:10px;color:#73869b}
.example-bites{display:grid;gap:8px}
.example-bite{display:grid;grid-template-columns:24px 1fr;gap:9px;align-items:start;padding:10px;background:#fff;border:1px solid #e1e9f1;border-radius:10px;font-size:12px;line-height:1.55}
.example-bite>span{display:grid;place-items:center;width:23px;height:23px;border-radius:7px;background:#e4edfc;color:#466bb5;font-weight:800;font-size:10px}
.revision-card-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:12px}
.revision-card-grid article{padding:12px;background:#f7f9fb;border:1px solid #e2e9ee;border-radius:12px;color:#31475b;font-size:11px}
.revision-card-grid article>span{display:block;color:#32877b;font-size:9px;font-weight:800;letter-spacing:1px;margin-bottom:5px}
.revision-card-grid article>strong{display:block;font-size:12px;margin-bottom:9px}
.revision-card-grid .concept-bite{font-size:10px;padding:7px;background:#fff}
.topic-test-question{border-radius:13px}
@media(max-width:720px){.visual-map-card{padding:14px 12px}.visual-map-heading strong{font-size:11px}.topic-diagram{max-height:150px}.learning-route{grid-template-columns:1fr}.learning-route>div{grid-template-columns:27px 1fr}.visual-note-section .section-content{padding:0 10px 12px}.visual-note-section summary{padding:11px;gap:8px}.revision-card-grid{grid-template-columns:1fr}.concept-bite{font-size:11px}}
@media print{.visual-map-card,.visual-callout,.visual-example,.visual-note-section,.revision-card-grid article{break-inside:avoid}.visual-note-section:not([open]) .section-content{display:block}.topic-video-card,.topic-test-actions,.screen-only{display:none!important}}

.illustration-gallery{margin:18px 0 23px}
.gallery-heading{display:flex;align-items:end;justify-content:space-between;gap:10px;margin-bottom:11px}
.gallery-heading h3{font:800 19px Manrope,sans-serif;color:var(--text);margin:3px 0 0}
.gallery-count{font-size:9px;letter-spacing:1px;font-weight:800;color:#6c8191}
.illustration-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}
.illustration-card{min-width:0;overflow:hidden;background:#fff;border:1px solid #e0e8ed;border-radius:15px;padding:10px;color:#30475a;box-shadow:0 4px 16px #102b3a08}
.illustration-art{display:grid;place-items:center;min-height:94px;background:linear-gradient(145deg,#f4f8fc,#eaf5f2);border-radius:10px;margin-bottom:10px}
.illustration-art svg{display:block;width:100%;max-width:150px;height:94px}
.illustration-label{display:block;color:#398579;font-size:8px;letter-spacing:1.2px;font-weight:800;margin-bottom:5px}
.illustration-card strong{display:block;font:750 12px Manrope,sans-serif;line-height:1.4;min-height:33px}
.illustration-caption{display:block;margin-top:5px;color:#8493a0;font-size:10px}
@media(max-width:720px){.illustration-grid{grid-template-columns:1fr}.illustration-card{display:grid;grid-template-columns:94px minmax(0,1fr);grid-template-rows:auto auto 1fr;column-gap:12px;align-items:start}.illustration-art{grid-row:1/4;min-height:90px;margin:0}.illustration-art svg{height:90px}.illustration-label{padding-top:3px}.illustration-card strong{min-height:0}.illustration-caption{margin-top:3px}}


/* NEW VISUAL IDENTITY: midnight plum, warm paper, coral and jade */
:root{
 --bg:#f6f3ef;
 --panel:#fffdfa;
 --panel-2:#f0ebe5;
 --text:#292638;
 --muted:#777180;
 --line:#e5ddd5;
 --primary:#b64f58;
 --primary-hover:#963e48;
 --accent:#347b70;
 --sidebar:#242237;
 --sidebar-text:#f5f0f7;
 --shadow:0 12px 34px rgba(42,30,47,.07);
}
body,.app-shell,.main-content{background:#f6f3ef!important;color:#292638}
.sidebar,.app-sidebar,.side-nav{background:#242237!important;color:#f5f0f7!important}
.sidebar .nav-link,.app-sidebar .nav-link,.side-nav a{color:#d6d0e0}
.sidebar .nav-link.active,.app-sidebar .nav-link.active,.side-nav .active{background:#3a354f!important;color:#fff!important;border-left-color:#e47d7c!important}
button.btn-primary,.btn-primary{background:#b64f58!important;border-color:#b64f58!important;color:#fff!important}
button.btn-primary:hover,.btn-primary:hover{background:#963e48!important}
.btn-secondary{background:#fffdfa!important;color:#423b50!important;border-color:#e5ddd5!important}
a{color:#347b70}
.card,.topic-card,.feature-card,.formula-card,.quiz-card,.note-section,.visual-note-section{background:#fffdfa;border-color:#e5ddd5}
.topic-hero{background:linear-gradient(120deg,#f4e9e3 0%,#f5f0e9 52%,#e5efeb 100%)!important;border-color:#e7d9d0!important}
.topic-hero-label,.section-kicker,.note-section-label{color:#a24b56!important}
.topic-hero-pills span{background:#e9e3ed;color:#50465f}
.topic-key-chip{background:#e3efea;border-color:#d0e4dc;color:#2e6d63}
.visual-map-card{background:#fffdfa;border-color:#e5ddd5}
.visual-map-heading span{background:#f4e2e0;color:#a34750}
.visual-map-caption{color:#777180;border-color:#e5ddd5}
.illustration-grid{grid-template-columns:repeat(3,minmax(0,1fr))}
.illustration-card{padding:10px;background:#fffdfa;border-color:#e5ddd5;box-shadow:0 8px 22px rgba(42,30,47,.05)}
.illustration-card .photo-link{display:block;overflow:hidden;border-radius:10px;margin-bottom:10px;background:#eee7e1}
.illustration-card .photo-link img{display:block;width:100%;height:145px;object-fit:cover;transition:transform .35s ease}
.illustration-card .photo-link:hover img{transform:scale(1.04)}
.illustration-label{color:#a24b56}
.illustration-card strong{color:#292638}
.illustration-caption,.gallery-count{color:#777180}
.image-credit{font-size:10px;line-height:1.5;color:#8b8490;margin:9px 0 0}
.image-credit a{color:#347b70;text-decoration:underline;text-underline-offset:2px}
.topic-photo-wrap{position:relative;overflow:hidden;border-radius:15px;background:#e8e0dc}
.topic-photo{display:block;width:100%;height:185px;object-fit:cover;border-radius:15px}
.topic-photo-caption{position:absolute;left:10px;bottom:10px;padding:6px 8px;border-radius:6px;background:rgba(36,34,55,.84);color:#fff;font-size:8px;font-weight:800;letter-spacing:1px}
.topic-wide-photo{display:block;width:100%;height:240px;object-fit:cover;border-radius:12px}
.visual-note-section summary:hover{background:#f6f0ed}
.visual-note-section .note-section-number{background:#f4e2e0;color:#a34750}
.section-toggle{background:#f0ebe5;color:#347b70}
.section-takeaway{border-left-color:#347b70;background:#e8f1ed}
.section-takeaway span{color:#347b70}
.concept-bite{background:#f8f4f0;border-color:#ece3dc;color:#3e3948}
.bite-dot{background:#f4e2e0;color:#a34750}
.visual-callout{background:#fff4df;border-color:#eddcb9;color:#5e4b2d}
.example-bite{border-color:#e5ddd5}
.example-bite>span{background:#f4e2e0;color:#a34750}
.learning-route>div>span{background:#e3efea;color:#347b70}
@media(max-width:720px){.illustration-grid{grid-template-columns:1fr}.illustration-card .photo-link img{height:185px}.topic-wide-photo{height:180px}}
@media(prefers-reduced-motion:reduce){.illustration-card .photo-link img{transition:none}}

/* Topic-specific embedded scientific images */
.topic-hero-art-text{display:flex;flex-direction:column;align-items:flex-start;justify-content:center;gap:14px;min-height:210px;padding:28px;border-radius:20px;background:radial-gradient(circle at 85% 20%,rgba(255,255,255,.16),transparent 35%),linear-gradient(145deg,#27243f,#347b70);color:#fff}
.topic-hero-art-text .hero-topic-code{font-size:11px;letter-spacing:.16em;font-weight:800;color:#d8e9e2}
.topic-hero-art-text strong{font-size:clamp(25px,3vw,38px);line-height:1.05;letter-spacing:-.04em}
.topic-hero-art-text>span:last-child{font-size:12px;opacity:.82}
.topic-visual-board{margin:24px 0 30px;padding:clamp(16px,2.4vw,28px);border:1px solid var(--line);border-radius:22px;background:var(--panel);box-shadow:var(--shadow)}
.topic-visual-heading{display:flex;flex-direction:column;gap:6px;margin-bottom:18px}
.topic-visual-heading>span{font-size:10px;font-weight:800;letter-spacing:.16em;color:var(--accent)}
.topic-visual-heading h3{font-size:clamp(22px,2.5vw,30px);margin:0;color:var(--text);letter-spacing:-.035em}
.topic-visual-heading p{margin:0;color:var(--muted);font-size:13px}
.topic-visual-grid{display:grid;grid-template-columns:minmax(0,1.25fr) minmax(0,1fr);gap:14px;align-items:stretch}
.topic-visual-card{margin:0;min-width:0;overflow:hidden;border:1px solid var(--line);border-radius:16px;background:var(--panel-2);display:flex;flex-direction:column}
.topic-visual-card img{display:block;width:100%;height:260px;object-fit:contain;background:#fff;padding:12px}
.topic-visual-main img{height:300px}
.topic-visual-card figcaption{display:flex;flex-direction:column;gap:7px;padding:16px 17px 18px}
.topic-visual-card figcaption strong{font-size:15px;line-height:1.3;color:var(--text)}
.topic-visual-card figcaption span{font-size:13px;line-height:1.6;color:var(--muted)}
.topic-visual-credit{font-size:10px;color:var(--muted);margin:14px 0 0}
@media(max-width:680px){.topic-visual-grid{grid-template-columns:1fr}.topic-visual-card img,.topic-visual-main img{height:220px}.topic-hero-art-text{min-height:150px}}
@media print{.topic-visual-board{break-inside:avoid}.topic-visual-card img{max-height:240px}}


/* GchemIB redesign · editorial science workspace */
:root{--bg:#f5f4ef;--panel:#fffefa;--panel2:#f0f2ed;--line:#e1e4dc;--text:#172d35;--muted:#687a7e;--teal:#087f75;--blue:#3158a6;--purple:#6d4ca3;--amber:#a56814;--radius:16px;--shadow:0 12px 35px #16332b0d}
html{scroll-behavior:smooth;background:var(--bg)}
body{background:var(--bg);color:var(--text);font-family:Inter,"DM Sans",Arial,sans-serif;font-size:14px;line-height:1.65}
button,input,select,textarea{font:inherit}
button{transition:background .18s,border-color .18s,transform .18s}
a{color:inherit}
.app-shell{background:var(--bg)}
.sidebar{width:248px;background:#142e35;border:0;padding:24px 15px 18px;color:#f4f7f3}
.brand{padding:0 9px 34px;gap:12px}
.brand-mark{border-radius:12px;background:#d6f36a;color:#142e35;box-shadow:none;font-size:24px}
.brand-copy strong{font-size:20px;color:#fff;font-family:Inter,Arial,sans-serif;letter-spacing:-.7px}
.brand-copy small{color:#a4bcb8;letter-spacing:1.3px;font-size:8px}
.sidebar-label{color:#91aaa7;letter-spacing:1.7px;padding-left:13px}
.side-nav{gap:4px}
.nav-link{padding:12px 13px;border-radius:10px;color:#b3c5c1;font-size:13px}
.nav-link:hover{background:#23444a;color:#fff}
.nav-link.active{background:#d6f36a;color:#173239;border-color:#d6f36a;font-weight:800}
.nav-link.active .nav-icon{color:#173239}
.nav-count{background:#2b4b50;color:#d9e8df}
.nav-link.active .nav-count{background:#b4d64e;color:#173239}
.mini-card{background:#1c3b40;border:1px solid #315458;border-radius:14px;padding:17px 15px}
.mini-card strong{font-size:13px;color:#fff}
.mini-card p{color:#b0c3bf;font-size:12px}
.text-button,.subtle-link{color:#477b32}
.sidebar .text-button{color:#d6f36a}
.sidebar-foot{color:#94aaa6}
.status-dot,.live-dot{background:#d6f36a;box-shadow:none}
.main-area{margin-left:248px}
.topbar{height:70px;padding:0 clamp(20px,3.2vw,48px);background:#f5f4efeF;border-bottom:1px solid #e0e3dc;backdrop-filter:blur(18px)}
.breadcrumbs{color:#84918d;font-size:12px}.breadcrumbs strong{color:#1b3339}
.global-search{background:#fffefa;border:1px solid #dfe4dc;border-radius:11px;color:#71827d}
.global-search input,.search-field input{color:#172d35}.global-search input::placeholder,.search-field input::placeholder{color:#98a39d}
.global-search kbd{border-color:#dce2d9;color:#788981}
.icon-button{background:#fffefa;border:1px solid #dfe4dc;color:#47605f}
.avatar{background:#d6f36a;border:0;color:#173239}
.language-toggle{background:#fffefa!important;border:1px solid #dfe4dc!important;color:#31554f!important;border-radius:9px!important}
.content-wrap{max-width:1580px;padding:clamp(20px,3.2vw,48px) clamp(18px,3.2vw,48px) 24px}
.page{animation:fadein .2s ease}
.hero{min-height:390px;border:0;border-radius:22px;background:#17383e;box-shadow:0 20px 50px #14363a15;grid-template-columns:1.1fr .9fr}
.hero-copy{padding:clamp(28px,4vw,55px) 0 35px clamp(25px,4vw,52px)}
.eyebrow{color:#c0d8c9;letter-spacing:1.7px;font-size:10px}
.eyebrow-dot{background:#d6f36a;box-shadow:none}
.hero h1{font-size:clamp(38px,4.3vw,60px);line-height:1.05;letter-spacing:-2.7px;color:#fff;margin:24px 0 18px}
.hero h1 span{color:#d6f36a}
.hero-copy>p{font-size:14px;line-height:1.8;color:#c0d0cb;max-width:430px}
.btn{border-radius:10px;padding:12px 17px;font-size:12px;font-weight:800}
.btn-primary{background:#d6f36a;color:#193338;box-shadow:none}
.btn-primary:hover{background:#e3ff86;transform:translateY(-1px)}
.btn-ghost{background:#23494d;border-color:#3d6263;color:#f4f8f2}
.btn-secondary{background:#fffefa;border-color:#dce3dc;color:#26464a}
.btn-secondary:hover{background:#edf3e9}
.hero-proof{color:#b4c9c2;font-size:11px}
.proof-avatars i{background:#d6f36a;color:#1b383b;border-color:#17383e}
.hero-visual:before{background:radial-gradient(ellipse,#2a777570,transparent 70%)}
.orb{border-color:#b4e9c933}
.visual-caption{background:#18383de8;border-color:#44666a;border-radius:12px}
.visual-caption strong{color:#fff}.visual-caption small{color:#b2c7c2}
.floating-chip{background:#24494e;border-color:#477074;color:#f5f7ef;box-shadow:none;border-radius:10px}
.floating-chip span{color:#d6f36a}
.section-heading{margin:38px 0 17px;align-items:center}
.section-heading h2{font-size:24px;letter-spacing:-.8px;color:#18363a}
.section-kicker,.feature-meta{color:#6d8580;letter-spacing:1.5px}
.feature-grid{gap:14px}
.feature-card{background:#fffefa;border:1px solid #e1e5dd;border-radius:15px;min-height:205px;padding:19px;box-shadow:0 4px 16px #19392e05}
.feature-card:hover{border-color:#a9c7a1;transform:translateY(-3px);background:#fff}
.feature-icon{border-radius:11px}
.feature-icon.teal{background:#e0f3e8;color:#087f75}
.feature-icon.blue{background:#e8eefc;color:#3158a6}
.feature-icon.purple{background:#f0eafb;color:#6d4ca3}
.feature-icon.amber{background:#f8edd9;color:#a56814}
.feature-meta{margin-top:15px}
.feature-card>strong{font-size:16px;color:#1a373c}
.feature-card p{font-size:12px;color:#6d7e7b;line-height:1.7}
.card-bottom{border-color:#edf0e9;color:#758680}
.card-bottom b{color:#087f75}
.lower-grid{gap:16px;margin-top:17px}
.panel{background:#fffefa;border:1px solid #e1e5dd;border-radius:16px;padding:22px;box-shadow:0 4px 18px #19392e04}
.panel h3{color:#1b383d;font-size:17px}
.panel p{font-size:12px;color:#6b7d79;line-height:1.75}
.panel-symbol{color:#087f75}
.progress-track,.quiz-progress-track{background:#e6ebe3}
.progress-track span,.quiz-progress-track span{background:#087f75}
.daily-options button{background:#f5f7f1;border:1px solid #e0e6dd;color:#31504d;border-radius:9px}
.daily-options button:hover{background:#e6f2df;border-color:#b7d2ad}
.inline-feedback{color:#087f75}
.page-intro{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin:0 0 25px}
.page-intro h1{font-size:clamp(32px,3.3vw,44px);letter-spacing:-1.8px;color:#18363a;margin:5px 0 8px}
.page-intro p{font-size:13px;color:#6c7d78;max-width:700px;margin:0}
.intro-stat{background:#e8f1df;border:1px solid #d8e6cc;border-radius:14px;padding:14px 20px;min-width:115px;text-align:center}
.intro-stat strong{display:block;font-size:28px;line-height:1.2;color:#244b3e}
.intro-stat span{font-size:10px;color:#648071}
.toolbar{display:flex;gap:12px;margin-bottom:17px}
.search-field{display:flex;align-items:center;gap:10px;min-height:44px;padding:0 13px;background:#fffefa;border:1px solid #dfe5dc;border-radius:11px;color:#6f837c}
.toolbar .search-field{flex:1}
select,.toolbar select{background:#fffefa;color:#27433f;border:1px solid #dfe5dc;border-radius:10px;padding:0 13px;min-height:44px}
.notes-layout{display:grid;grid-template-columns:minmax(230px,290px) minmax(0,1fr);gap:17px;align-items:start}
.topic-list{background:#fffefa;border:1px solid #e1e5dd;border-radius:15px;padding:9px;max-height:calc(100vh - 160px);overflow:auto}
.topic-item,.topic-list button{border-radius:10px}
.topic-item{border:1px solid transparent;padding:12px 13px;margin:3px 0;background:transparent;color:#526963}
.topic-item:hover{background:#f3f6ef}
.topic-item.active{background:#eaf3e3;border-color:#d7e7cb;color:#1b453d}
.topic-item strong{color:#203b3c}
.topic-item small,.topic-item p{color:#778983}
.note-reader{min-width:0;background:transparent;border:0;padding:0}
.empty-state{background:#fffefa;border:1px dashed #cdd9cc;border-radius:16px;padding:50px 24px;color:#6c817a}
.topic-hero{border:0;border-radius:18px;background:#e7f0df;overflow:hidden;box-shadow:0 8px 26px #1b47350a}
.topic-hero-copy{padding:clamp(22px,3vw,36px)}
.topic-hero-label{color:#577a61;letter-spacing:1.5px}
.topic-hero h2{font-size:clamp(28px,3vw,40px);line-height:1.14;letter-spacing:-1.3px;color:#193a3c}
.topic-key-chip{background:#fffefa;border:1px solid #dbe7d3;color:#315a4e;border-radius:30px;padding:5px 10px}
.topic-hero-pills span{background:#d6e7ca;color:#476a59;border-radius:6px}
.topic-hero-art{background:#17383e;color:#d6f36a}
.visual-diagram,.topic-diagram,.diagram-card{border-radius:15px;overflow:hidden}
.note-meta{color:#81918a;border-bottom:1px solid #dfe5dc}
.topic-video-card{background:#fffefa;border:1px solid #dfe5dc;border-radius:14px;padding:16px}
.video-icon{background:#e0f3e8;color:#087f75;border-radius:11px}
.topic-video-copy strong{color:#203d3e}.topic-video-copy p{color:#71817c}
.note-learning{background:#17383e;color:#fff;border-radius:15px;padding:20px}
.note-learning h3{color:#d6f36a}
.learning-route>div{background:#21464a;border:1px solid #386065;border-radius:11px}
.learning-route>div span{background:#d6f36a;color:#17383e}
.learning-route strong{color:#fff}.learning-route small{color:#b5c9c2}
.note-section-list{margin-top:28px}
.notes-list-heading h3{font-size:25px;color:#1b383d;letter-spacing:-.7px}
.notes-list-heading p{color:#70817b}
.visual-note-section{background:#fffefa;border:1px solid #e1e6dd;border-radius:13px;margin:10px 0;overflow:hidden}
.visual-note-section[open]{border-color:#c6d9bd;box-shadow:0 5px 18px #1c493108}
.visual-note-section summary{padding:17px 19px;gap:14px}
.note-section-number{background:#eaf2e3;color:#2d674d;border-radius:8px}
.note-section-label{color:#7c9285}
.section-summary-copy strong{color:#1b393b;font-size:15px}
.section-toggle{color:#087f75}
.section-content{padding:0 20px 20px 56px;color:#455f5a}
.concept-bites{gap:10px}
.concept-bites li{color:#405b55;line-height:1.75}
.bite-dot{background:#e1f1df;color:#28744c;border-radius:7px}
.section-takeaway{background:#f0f5e9;border-left:3px solid #8ebd6c;border-radius:0 8px 8px 0;padding:12px 14px}
.section-takeaway span{color:#6d8b5b}.section-takeaway strong{color:#31523e}
.note-callout{background:#fff5e5;border:1px solid #f0dfc2;border-radius:13px;color:#674c26}
.callout-icon{background:#f5dfb7;color:#8e5b16;border-radius:9px}
.callout-bite{color:#6d5839}
.example-box{background:#eaf2fb;border:1px solid #d8e4f3;border-radius:13px}
.example-heading strong{color:#294b7e}.example-heading small{color:#6d83a5}
.example-bite>span{background:#d7e5f8;color:#3158a6}
.example-bite>div{color:#344e70}
.topic-test{background:#fffefa;border:1px solid #e1e5dd;border-radius:15px;padding:22px}
.test-heading h3{font-size:24px;color:#1b383d}
.test-heading p{color:#6e807a}
.topic-test-question{border:1px solid #e1e7de;background:#fbfcf8;border-radius:12px;padding:16px}
.test-question-meta{color:#6e897a}
.topic-test-question h4{color:#294542}
.written-answer{background:#fff;border:1px solid #dce4da;border-radius:9px;color:#243f3b;width:100%;padding:11px}
.answer-hint{color:#7c8b83}
.model-answer{background:#f0f5e9;border-radius:12px;padding:16px}
.revision-card-grid article{background:#fffefa;border:1px solid #dfe8d8;border-radius:10px;padding:13px;color:#456057}
.revision-card-grid article strong{color:#20443b}
.note-footer{color:#7d8e86;border-top:1px solid #dfe5dc}
.sequence-note{background:#fff5e5;border:1px solid #efdfc4;color:#6a542e;border-radius:13px}
.sequence-term{background:#fffefa;border:1px solid #e1e5dd;border-radius:15px;overflow:hidden;margin:15px 0}
.sequence-term-head{background:#eaf2e3;color:#244c3d;padding:18px 21px}
.sequence-term-head h2{color:#1c4139}
.sequence-table th{background:#f5f7f1;color:#687d72}
.sequence-table td{border-color:#e6eae2;color:#405751}
.sequence-table tr:hover td{background:#f8faf5}
.formula-card{background:#fffefa;border:1px solid #e1e5dd;border-radius:14px;padding:18px}
.formula-card h3{color:#1e3c3c}.formula-tag{background:#e8f2e0;color:#4b7351;border-radius:6px}
.equation{background:#f0f5e9;border:1px solid #e1ead9;border-radius:10px;color:#1d564a}
.formula-card p{color:#5d726b}.formula-example{background:#f4f7f0;border-radius:9px;color:#62746a}
.periodic-toolbar{gap:12px}
.periodic-wrap{background:#fffefa;border:1px solid #e1e5dd;border-radius:15px;padding:15px;overflow:auto}
.periodic-grid .element{border-radius:5px;border-color:#fffefa}
.element-detail{background:#fffefa;border:1px solid #e1e5dd;border-radius:14px;color:#264441}
.detail-symbol{background:#e0f3e8;color:#087f75;border-radius:12px}
.practice-layout{gap:16px}
.practice-main,.practice-side{background:#fffefa;border:1px solid #e1e5dd;border-radius:15px}
.quiz-top{color:#72847d}
.tiny-pill{background:#e8f2e0;color:#47734c}
.quiz-option{background:#f7f8f3;border:1px solid #dfe5dc;color:#294641;border-radius:10px}
.quiz-option:hover{background:#eaf3e4;border-color:#b9d2ae}
.quiz-option.correct{background:#e0f4df;border-color:#8fc58b;color:#225a37}
.quiz-option.incorrect{background:#fff0e9;border-color:#e5b7a7;color:#8e3d28}
.tool-grid{gap:15px}
.calculator-card{background:#fffefa;border:1px solid #e1e5dd;border-radius:15px}
.calculator-card label{color:#47645c}
.calculator-card input{background:#fbfcf8;border:1px solid #dfe5dc;border-radius:9px;color:#1d3939;padding:11px}
.result-box{background:#edf4e7;border:1px solid #dce8d3;border-radius:10px;color:#245747}
.helper-text{color:#7d8c83}
.tutor-chat,.tutor-guide,.privacy-note{background:#fffefa;border:1px solid #e1e5dd;border-radius:15px}
.chat-header{border-bottom:1px solid #e4e9e0}
.chat-header strong{color:#1d3c3b}.chat-header small{color:#758780}
.ai-avatar{background:#e0f3e8;color:#087f75;border-radius:11px}
.chat-messages{background:#f8f9f5;border-radius:12px}
.message.assistant .message-body{background:#fff;border:1px solid #e1e7de;color:#36514b;border-radius:0 12px 12px 12px}
.message.user .message-body{background:#e5f2dc;color:#254b3c;border-radius:12px 0 12px 12px}
.message-body p{color:inherit}
.suggestion-chips button{background:#f0f5e9;border:1px solid #dce7d5;color:#41674f;border-radius:20px}
.chat-compose{border:1px solid #dce4da;background:#fff;border-radius:12px}
.chat-compose textarea{color:#1c3839}
.send-button{background:#17383e;color:#d6f36a;border-radius:9px}
.chat-disclaimer{color:#84938b}
.ai-status{background:#e6f3e1;color:#43784a;border-radius:20px;padding:7px 11px}
.ai-status i{background:#4baf66}
.site-footer{border-top:1px solid #dfe5dc;color:#819089}
.brand-mini{color:#24433e}
.toast{background:#17383e;color:#fff;border:1px solid #31585a;border-radius:10px}
body.high-contrast{--bg:#fff;--panel:#fff;--panel2:#f7f7f7;--text:#111;--muted:#444}
@media(max-width:1100px){.feature-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.content-wrap{padding:24px}.topbar{padding:0 24px}.hero{grid-template-columns:1fr .8fr}.notes-layout{grid-template-columns:240px minmax(0,1fr)}}
@media(max-width:820px){.sidebar{transform:translateX(-100%);transition:transform .22s;box-shadow:none}.sidebar.open{transform:translateX(0);box-shadow:18px 0 50px #071c1b30}.main-area{margin-left:0}.mobile-menu{display:block}.topbar{gap:12px;padding:0 16px}.breadcrumbs{margin-right:auto}.global-search{width:min(36vw,210px)}.avatar{display:none}.content-wrap{padding:19px 15px}.hero{grid-template-columns:1fr}.hero-copy{padding:28px 24px 12px}.hero-visual{min-height:280px}.hero h1{font-size:42px}.feature-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.lower-grid{grid-template-columns:1fr}.notes-layout{grid-template-columns:1fr}.topic-list{max-height:260px;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:3px}.topic-item{min-width:0}.page-intro{align-items:flex-start}.intro-stat{min-width:85px;padding:10px}.intro-stat strong{font-size:23px}}
@media(max-width:520px){.topbar{height:62px}.breadcrumbs span:first-child,.crumb-slash{display:none}.global-search{width:38vw;height:35px}.top-actions{gap:6px}.language-toggle{padding:7px!important}.hero h1{font-size:37px}.hero-visual{min-height:245px}.floating-chip{font-size:9px;padding:6px 8px}.chip-top{right:10px}.chip-bottom{left:5px}.visual-caption{right:10px;bottom:10px}.feature-grid{grid-template-columns:1fr 1fr;gap:9px}.feature-card{padding:13px;min-height:185px}.feature-card>strong{font-size:14px}.feature-card p{font-size:11px}.section-heading h2{font-size:20px}.page-intro h1{font-size:32px}.page-intro{gap:10px}.intro-stat{display:none}.toolbar{flex-direction:column}.toolbar select{min-height:42px}.topic-list{grid-template-columns:1fr 1fr}.topic-item{padding:10px}.topic-hero-art{min-height:170px}.section-content{padding:0 14px 17px}.visual-note-section summary{padding:14px}.learning-route{gap:8px}.learning-route>div{padding:10px}.learning-route small{font-size:10px}.practice-layout{grid-template-columns:1fr}.field-row{grid-template-columns:1fr}.site-footer{gap:10px;flex-wrap:wrap}}
@media print{.sidebar,.topbar,.note-actions,.topic-video-card,.note-learning,.screen-only,.site-footer{display:none!important}.main-area{margin:0}.content-wrap{padding:0}.page{display:none!important}#page-notes{display:block!important}.note-reader{display:block}.visual-note-section{break-inside:avoid}.visual-note-section .section-content{display:block!important}}


/* Topic navigation and note reading refinements */
.topic-button{display:flex;align-items:flex-start;gap:11px;width:100%;text-align:left;border:1px solid transparent;background:transparent;color:#526963;padding:12px 11px;margin:3px 0;border-radius:11px}
.topic-button:hover{background:#f3f6ef}
.topic-button.active{background:#eaf3e3;border-color:#d7e7cb;color:#1b453d}
.topic-button strong{display:block;font-size:12px;line-height:1.4;color:#203b3c}
.topic-button small{display:block;font-size:10px;line-height:1.5;color:#778983;margin-top:4px}
.topic-index{display:grid;place-items:center;flex:0 0 30px;height:30px;background:#f0f3ed;color:#6e8177;border-radius:8px;font-size:10px;font-weight:800}
.topic-button.active .topic-index{background:#d6f36a;color:#23443a}
.note-reader .visual-diagram{margin:15px 0}
.note-reader img{max-width:100%;height:auto;border-radius:12px}
.note-reader p{line-height:1.8}
.note-reader .concept-bites{list-style:none;padding:0;margin:12px 0 16px;display:grid;gap:11px}
.note-reader .concept-bites li{display:grid;grid-template-columns:28px minmax(0,1fr);gap:10px;align-items:start}
.note-reader .bite-dot{width:27px;height:27px;display:grid;place-items:center;font-size:10px;font-weight:800}
@media(max-width:520px){.topic-button{padding:9px}.topic-button strong{font-size:11px}.topic-button small{font-size:9px}}

/* GchemIB study-guide layout: editorial, visual, and easy to scan */
.study-topline{display:flex;align-items:center;gap:12px;margin:0 0 14px;min-height:30px}
.study-subject-mark{font-size:11px;font-weight:900;letter-spacing:1.7px;color:#193b3e}
.study-subject-mark span{color:#8bbd60;font-size:17px;padding:0 2px}
.study-level-mark{font-size:9px;letter-spacing:1.4px;color:#71867b;margin-right:auto}
.study-topline .print-note{padding:8px 12px;font-size:10px}
.study-hero{position:relative;display:grid;grid-template-columns:minmax(0,1.35fr) minmax(190px,.65fr);min-height:290px;overflow:hidden;background:#17383e;border-radius:20px;color:#f6f8ef;box-shadow:0 16px 38px #17383e16}
.study-hero-copy{position:relative;z-index:2;padding:clamp(24px,3.3vw,40px)}
.study-eyebrow,.study-section-overline{font-size:9px;font-weight:850;letter-spacing:1.8px;color:#668779}
.study-eyebrow{display:flex;align-items:center;gap:8px;color:#b8d1c6}
.study-live-dot{width:7px;height:7px;border-radius:50%;background:#d6f36a;box-shadow:0 0 0 4px #d6f36a20}
.study-hero h1{font-size:clamp(30px,3.3vw,46px);line-height:1.08;letter-spacing:-1.7px;color:#fff;margin:19px 0 13px;max-width:560px}
.study-hero-copy>p{font-size:12px;line-height:1.85;color:#c3d3cc;max-width:540px;margin:0}
.study-topic-chips{display:flex;flex-wrap:wrap;gap:7px;margin-top:17px}
.study-topic-chips .topic-key-chip{background:#24494c;border:1px solid #3a6260;color:#e3eee4;font-size:10px}
.study-hero-bottom{display:flex;align-items:center;gap:10px;margin-top:26px;color:#90b0a3;font-size:8px;letter-spacing:1px}
.study-hero-bottom b{color:#d9e9d9;font-weight:800}
.study-hero-bottom i{height:1px;width:19px;background:#4c7470}
.study-hero-art{position:relative;min-height:245px;overflow:hidden;background:radial-gradient(circle at 50% 48%,#397d70 0,#24544f 32%,#17383e 70%)}
.study-art-orbit{position:absolute;border:1px solid #b5e5c533;border-radius:50%;left:50%;top:48%;transform:translate(-50%,-50%) rotate(-25deg)}
.orbit-one{width:245px;height:125px}.orbit-two{width:195px;height:195px;transform:translate(-50%,-50%) rotate(32deg)}
.study-art-core{position:absolute;left:50%;top:48%;transform:translate(-50%,-50%);width:105px;height:105px;border-radius:50%;display:flex;flex-direction:column;align-items:center;justify-content:center;background:#d6f36a;color:#18383b;box-shadow:0 0 0 12px #d6f36a18,0 0 50px #d6f36a30}
.study-art-core span{font-size:9px;letter-spacing:2px}.study-art-core strong{font-size:22px;letter-spacing:-1px;line-height:1.2}.study-art-core small{font-size:8px;letter-spacing:1.5px;margin-top:4px}
.study-art-label{position:absolute;font-size:8px;font-weight:800;letter-spacing:1.1px;color:#e4f0dd;background:#20484a;border:1px solid #4b7771;border-radius:7px;padding:7px 9px}
.art-label-one{top:15%;left:8%}.art-label-two{right:7%;top:32%}.art-label-three{bottom:15%;left:26%}
.study-roadmap{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:9px;margin:12px 0 25px}
.study-roadmap>div{display:flex;align-items:center;gap:11px;padding:13px;background:#fffefa;border:1px solid #e1e7dd;border-radius:12px}
.roadmap-icon{display:grid;place-items:center;flex:0 0 32px;height:32px;border-radius:9px;background:#e7f2df;color:#34724c;font-size:10px;font-weight:900}
.study-roadmap strong{display:block;color:#24443e;font-size:9px;letter-spacing:.5px}
.study-roadmap p{margin:3px 0 0;font-size:10px;line-height:1.5;color:#77877e}
.study-big-idea{padding:22px 24px;margin:0 0 31px;background:#e8f1df;border:1px solid #d8e7cd;border-radius:15px}
.study-big-idea-grid{display:grid;grid-template-columns:minmax(0,1.25fr) minmax(180px,.75fr);gap:20px;align-items:center;margin-top:9px}
.study-big-idea h2{font-size:23px;letter-spacing:-.7px;line-height:1.2;color:#203e37;margin:0 0 9px}
.study-big-idea-grid>div:first-child>p{font-size:12px;line-height:1.85;color:#526e5d;margin:0}
.study-big-idea-stamp{padding:16px 18px;background:#fffefa;border:1px solid #d7e4ce;border-radius:12px}
.study-big-idea-stamp span{display:block;font-size:8px;letter-spacing:1.5px;color:#7c9880;font-weight:900;margin-bottom:7px}
.study-big-idea-stamp strong{display:block;font-size:15px;line-height:1.4;color:#28513e}
.study-big-idea-stamp small{display:block;font-size:10px;color:#7b8c7c;margin-top:8px}
.study-section-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:16px;margin:0 0 15px}
.study-section-heading h2,.study-practice-heading h2{font-size:clamp(24px,2.6vw,32px);letter-spacing:-1px;line-height:1.15;color:#1d3b3b;margin:6px 0 8px}
.study-section-heading p,.study-practice-heading p{font-size:12px;color:#72827a;margin:0;line-height:1.7}
.study-count{flex:0 0 auto;font-size:9px;letter-spacing:1px;color:#698373;background:#e8f1df;padding:8px 10px;border-radius:7px}
.study-concept-list{display:grid;gap:12px}
.study-concept-card{display:grid;grid-template-columns:62px minmax(0,1fr);gap:17px;padding:22px 23px;background:#fffefa;border:1px solid #e1e7dd;border-radius:15px;box-shadow:0 4px 14px #1d453707}
.study-concept-card:nth-child(3n+2){background:#fcfdf8}
.study-concept-number{display:grid;place-items:center;width:48px;height:48px;border-radius:14px;background:#e4f1dc;color:#34724c;font-size:17px;font-weight:900}
.study-concept-card:nth-child(3n+2) .study-concept-number{background:#e8edfb;color:#405fa2}
.study-concept-card:nth-child(3n) .study-concept-number{background:#f7ebd9;color:#a56c1c}
.study-concept-kicker{font-size:8px;letter-spacing:1.5px;color:#829286;font-weight:900;margin:1px 0 5px}
.study-concept-content h3{font-size:19px;line-height:1.3;letter-spacing:-.4px;color:#203e3b;margin:0 0 10px}
.study-concept-content>p{font-size:12px;color:#465f55;line-height:1.9}
.study-concept-content .concept-bites{display:grid;gap:10px;margin:10px 0 0}
.study-concept-content .concept-bite{display:grid;grid-template-columns:25px minmax(0,1fr);gap:10px;align-items:start;font-size:12px;line-height:1.85;color:#4a6158}
.study-concept-content .bite-dot{display:grid;place-items:center;width:24px;height:24px;border-radius:7px;background:#eff4e9;color:#4b7954;font-size:9px;font-weight:900}
.study-mini-summary{display:grid;grid-template-columns:auto minmax(0,1fr);gap:12px;align-items:start;margin-top:15px;padding:12px 14px;background:#f1f6eb;border-radius:9px;border-left:3px solid #a6c987}
.study-mini-summary span{font-size:8px;letter-spacing:1px;font-weight:900;color:#5d8554;padding-top:3px}
.study-mini-summary p{font-size:11px;line-height:1.7;color:#4c6b50;margin:0}
.study-example-panel{position:relative;overflow:hidden;margin-top:27px;padding:24px;background:#eaf0fb;border:1px solid #d9e3f4;border-radius:16px}
.study-panel-label{display:inline-flex;align-items:center;gap:8px;padding:6px 9px;background:#d9e5fa;color:#3b5d98;border-radius:7px;font-size:8px;letter-spacing:1.2px;font-weight:900}
.study-panel-label span{font-size:14px}
.study-example-grid{display:grid;grid-template-columns:minmax(0,.85fr) minmax(0,1.15fr);gap:25px;margin-top:20px}
.study-example-grid h2,.study-exam-panel h2{font-size:22px;line-height:1.2;letter-spacing:-.6px;color:#2b4776;margin:7px 0 10px}
.study-example-grid>div:first-child>p{font-size:11px;line-height:1.8;color:#5b7193}
.study-example-point{display:grid;grid-template-columns:29px minmax(0,1fr);gap:10px;padding:12px 0;border-bottom:1px solid #d6e1f1}
.study-example-point:first-child{padding-top:0}.study-example-point:last-child{border-bottom:0;padding-bottom:0}
.study-example-point>span{display:grid;place-items:center;width:26px;height:26px;border-radius:8px;background:#d6e4f8;color:#365d9b;font-size:9px;font-weight:900}
.study-example-point p{margin:0;font-size:12px;line-height:1.8;color:#3f5679}
.study-exam-panel{display:grid;grid-template-columns:44px minmax(0,1fr);gap:14px;margin-top:13px;padding:20px 22px;background:#fff5e5;border:1px solid #f0dfc2;border-radius:14px}
.study-exam-icon{display:grid;place-items:center;width:38px;height:38px;border-radius:12px;background:#f5dfb7;color:#8c5b17;font-size:21px;font-weight:900}
.study-exam-panel h2{font-size:19px;color:#725322;margin:5px 0 7px}
.study-exam-points p{font-size:11px;line-height:1.8;color:#715e3d;margin:7px 0 0}
.study-video-panel{display:flex;align-items:center;gap:15px;margin-top:13px;padding:17px 19px;background:#fffefa;border:1px solid #e1e7dd;border-radius:14px}
.study-video-symbol{display:grid;place-items:center;flex:0 0 43px;height:43px;border-radius:12px;background:#e1f2df;color:#147b6a;font-size:15px}
.study-video-copy{flex:1;min-width:0}.study-video-copy h3{font-size:14px;color:#23423c;margin:4px 0 4px}.study-video-copy p{font-size:10px;line-height:1.6;color:#78877e;margin:0}
.study-video-panel .btn{white-space:nowrap}
.study-practice-panel{margin-top:27px;padding:23px;background:#17383e;border-radius:17px;color:#f3f7ef}
.study-practice-panel .study-section-overline{color:#c2dcbd}
.study-practice-heading{display:flex;align-items:flex-start;justify-content:space-between;gap:14px;margin:8px 0 18px}
.study-practice-heading h2{color:#fff;margin:0 0 8px}
.study-practice-heading p{color:#bdd0c5}
.study-practice-badge{flex:0 0 auto;padding:7px 9px;border:1px solid #456a60;border-radius:7px;color:#d6f36a;font-size:8px;letter-spacing:1px}
.study-practice-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}
.study-practice-card{padding:15px;background:#21464a;border:1px solid #3a6261;border-radius:12px}
.study-practice-meta{display:flex;align-items:center;gap:8px;color:#d6f36a;font-size:9px}
.study-practice-meta span{display:grid;place-items:center;width:24px;height:24px;border-radius:7px;background:#d6f36a;color:#17383e;font-weight:900}
.study-practice-meta strong{letter-spacing:1px}
.study-practice-card h4{font-size:12px;line-height:1.6;color:#f4f7ef;margin:12px 0}
.study-practice-card .written-answer{width:100%;box-sizing:border-box;background:#17383e;border:1px solid #456a60;border-radius:8px;padding:9px;color:#fff;font-size:11px}
.study-practice-card .written-answer::placeholder{color:#9ab5a9}
.study-practice-card>p{font-size:10px;line-height:1.6;color:#aec6bb;margin:8px 0 0}
.study-practice-actions{display:flex;gap:9px;margin-top:14px}
.study-practice-actions .btn-secondary{background:#24494c;border-color:#456a60;color:#f1f6ec}
.study-practice-panel .model-answer{margin-top:14px;background:#21464a;border:1px solid #3a6261;color:#f4f7ef}
.study-practice-panel .model-answer h3{color:#d6f36a}
.study-revision-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}
.study-revision-grid article{background:#17383e;border:1px solid #456a60;border-radius:9px;padding:13px;color:#c6d9cf;font-size:11px;line-height:1.7}
.study-revision-grid article>span{display:block;color:#d6f36a;font-size:9px;margin-bottom:6px}
.study-revision-grid article strong{display:block;color:#fff;margin-bottom:6px}
.study-note-footer{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:18px 2px;margin-top:12px;border-top:1px solid #dfe5dc;color:#7b8b81}
.study-note-footer>span:first-child{font-weight:900;letter-spacing:1px;color:#23433c}
.study-note-footer>span:nth-child(2){font-size:8px;letter-spacing:1.2px}
.study-note-footer .btn{font-size:9px;padding:7px 10px}
@media(max-width:900px){.study-hero{grid-template-columns:minmax(0,1fr) 220px}.study-hero h1{font-size:34px}.study-roadmap{grid-template-columns:1fr}.study-roadmap>div{padding:10px 13px}.study-practice-grid{grid-template-columns:1fr}.study-practice-card{display:grid;grid-template-columns:1fr;}}
@media(max-width:620px){.study-topline{flex-wrap:wrap}.study-hero{grid-template-columns:1fr}.study-hero-copy{padding:24px 21px 17px}.study-hero h1{font-size:34px}.study-hero-art{min-height:205px}.study-art-core{width:88px;height:88px}.study-art-core strong{font-size:18px}.study-big-idea{padding:19px}.study-big-idea-grid,.study-example-grid{grid-template-columns:1fr;gap:15px}.study-section-heading{align-items:flex-start}.study-count{font-size:8px}.study-concept-card{grid-template-columns:38px minmax(0,1fr);gap:11px;padding:16px 13px}.study-concept-number{width:36px;height:36px;border-radius:10px;font-size:12px}.study-concept-content h3{font-size:17px}.study-mini-summary{grid-template-columns:1fr;gap:4px}.study-example-panel{padding:18px}.study-exam-panel{padding:16px;grid-template-columns:34px minmax(0,1fr);gap:10px}.study-exam-icon{width:32px;height:32px}.study-video-panel{flex-wrap:wrap;align-items:flex-start}.study-video-copy{min-width:calc(100% - 62px)}.study-video-panel .btn{margin-left:58px}.study-practice-panel{padding:18px 13px}.study-practice-heading{display:block}.study-practice-badge{display:inline-block;margin-top:10px}.study-practice-actions{flex-wrap:wrap}.study-revision-grid{grid-template-columns:1fr}.study-note-footer{flex-wrap:wrap}.study-note-footer>span:nth-child(2){order:3;width:100%}}
@media print{.study-hero{background:#fff!important;color:#111;border:1px solid #ddd;box-shadow:none}.study-hero h1,.study-practice-heading h2{color:#111}.study-hero-copy>p,.study-eyebrow{color:#444}.study-hero-art,.study-roadmap,.study-video-panel,.study-practice-actions,.study-topline .print-note,.study-note-footer .btn{display:none!important}.study-concept-card,.study-big-idea,.study-example-panel,.study-exam-panel{break-inside:avoid;box-shadow:none}}


/* GchemIB visual atlas redesign */
:root{--bg:#f6f4ef;--panel:#fffefa;--panel2:#f0eee8;--line:#e6e1d7;--text:#242b42;--muted:#777d8d;--teal:#2b9e8f;--blue:#7165d9;--purple:#a78bfa;--amber:#fb9364;--radius:22px;--shadow:0 12px 36px #29304b0c}
body{background:#f6f4ef;color:#242b42;font-family:"DM Sans",sans-serif}
.sidebar{background:#202743;border:0;color:#f7f5f0;box-shadow:10px 0 45px #20274312}
.brand-mark{background:#ff9c6c;color:#202743;box-shadow:none;border-radius:14px}
.brand-copy strong{font-family:"Manrope",sans-serif;letter-spacing:-.04em}.brand-copy small{color:#b5bad0;letter-spacing:.14em}
.sidebar-label{color:#a7aec8}.nav-link{color:#c4c9db;border-radius:13px}.nav-link:hover{background:#ffffff0d;color:#fff}.nav-link.active{background:#ff9c6c;color:#202743;box-shadow:none}.nav-link.active .nav-icon{color:#202743}
.mini-card{background:#303957;border:1px solid #454d6b;border-radius:18px}.mini-card p{color:#c4c9db}.text-button{color:#ffb28c}.sidebar-foot{color:#a7aec8}
.main-area{margin-left:246px;background:#f6f4ef}.topbar{background:#f6f4efed;border-bottom:1px solid #e8e3da;backdrop-filter:blur(18px)}
.breadcrumbs{color:#8a8c9a}.breadcrumbs strong{color:#242b42}.global-search{background:#fffefa;border-color:#e7e2d9;border-radius:14px}
.icon-button{background:#fffefa;border-color:#e7e2d9;color:#303653;border-radius:12px}.avatar{background:#7165d9;color:#fff;border-radius:14px}
.content-wrap{max-width:1560px;padding:32px 38px 24px}
.hero{background:#202743;border:0;border-radius:30px;overflow:hidden;position:relative;box-shadow:0 18px 50px #2027431a}
.hero:before{content:"";position:absolute;width:420px;height:420px;border:1px solid #ffffff16;border-radius:50%;right:8%;top:-44%;box-shadow:0 0 0 42px #ffffff06,0 0 0 84px #ffffff04}
.hero-copy{padding:48px 0 44px 48px;position:relative;z-index:1}.hero h1{font-family:"Manrope",sans-serif;font-size:clamp(36px,4.2vw,62px);line-height:1.03;letter-spacing:-.06em}.hero h1 span{color:#ffab7d}.hero-copy>p{color:#c5c9d9;max-width:400px}.eyebrow{color:#aeb5d1;letter-spacing:.16em}.eyebrow-dot{background:#ff9c6c}
.btn-primary{background:#ff9c6c;color:#202743;border-color:#ff9c6c;box-shadow:none}.btn-primary:hover{background:#ffb28c}.btn-ghost{color:#fff;border-color:#ffffff38;background:#ffffff08}.hero-proof{color:#bfc5d8}.proof-avatars i{background:#62c9b6;color:#202743;border-color:#202743}.proof-avatars i:nth-child(2){background:#ff9c6c}.proof-avatars i:nth-child(3){background:#a99bf3}
.hero-visual{background:radial-gradient(ellipse at center,#3a4265 0%,#202743 65%)}.orb-one{background:#ff9c6c}.orb-two{background:#62c9b6}.orb-three{background:#a99bf3}.visual-caption{background:#303957;border:1px solid #454d6b;color:#fff}.visual-caption small{color:#c4c9db}.floating-chip{background:#303957;color:#f7f5f0;border:1px solid #454d6b;box-shadow:none}
.section-heading h2,.page-intro h1{font-family:"Manrope",sans-serif;letter-spacing:-.045em}.section-kicker{color:#7165d9;letter-spacing:.16em}.feature-card,.panel,.feature-grid .feature-card{background:#fffefa;border:1px solid #e9e4db;border-radius:20px;box-shadow:0 5px 18px #29304b05}.feature-card:hover{border-color:#b5aef1;transform:translateY(-3px);box-shadow:0 14px 30px #29304b0c}.feature-icon.teal{background:#dff4ee;color:#278e7e}.feature-icon.blue{background:#e9e7ff;color:#6559cb}.feature-icon.purple{background:#f2e6fc;color:#a260c5}.feature-icon.amber{background:#ffeadc;color:#d97745}
.site-footer{border-color:#e5dfd5;color:#85899a}
.page-intro p,.section-heading p{color:#777d8d}
#page-notes .notes-layout{gap:22px}
.notes-sidebar{background:#fffefa;border:1px solid #e9e4db;border-radius:22px}
.topic-button{border-radius:14px}.topic-button:hover{background:#f4f1eb}.topic-button.active{background:#fce8dc;border-color:#f7c4a6;color:#282d43}.topic-index{background:#eeece5;color:#7165d9}
.notes-reader{background:transparent}
#note-reader{display:flex;flex-direction:column;gap:22px}
.atlas-toolbar{display:flex;align-items:center;justify-content:space-between;padding:5px 0 0}
.atlas-mark{display:flex;align-items:center;gap:10px;font-family:"Manrope",sans-serif;font-size:15px;letter-spacing:-.04em}.atlas-mark span{width:31px;height:31px;display:grid;place-items:center;border-radius:10px;background:#202743;color:#ff9c6c;font-size:20px;font-weight:900}
.atlas-toolbar-actions{display:flex;align-items:center;gap:10px}.atlas-level{border:1px solid #e6e1d7;background:#fffefa;border-radius:100px;padding:8px 12px;color:#7165d9;font-size:10px;font-weight:800;letter-spacing:.1em}.atlas-icon-btn{border:1px solid #e6e1d7;background:#fffefa;border-radius:12px;width:38px;height:38px;color:#242b42;font-size:18px}
.atlas-hero{min-height:300px;position:relative;display:grid;grid-template-columns:1.15fr .85fr;overflow:hidden;border-radius:28px;background:#e7e4fb;border:1px solid #dad5f5;padding:34px 38px;color:#252b45}
.atlas-hero:after{content:"";position:absolute;inset:auto -10% -72% 22%;height:260px;border-radius:50%;background:#d3cdf7;pointer-events:none}
.atlas-hero-copy{position:relative;z-index:1;align-self:center}
.atlas-kicker,.atlas-section-title>div>span{font-size:10px;font-weight:900;letter-spacing:.16em;color:#7165d9}.atlas-kicker{display:flex;align-items:center;gap:8px}.atlas-kicker span{width:7px;height:7px;border-radius:50%;background:#ff9368;box-shadow:0 0 0 4px #ff93682a}
.atlas-hero h1{font-family:"Manrope",sans-serif;font-size:clamp(27px,3.2vw,46px);line-height:1.07;letter-spacing:-.06em;max-width:600px;margin:17px 0 22px}
.atlas-keywords{display:flex;flex-wrap:wrap;gap:7px}.atlas-keyword{padding:7px 11px;background:#fffefa;border:1px solid #d8d2f4;border-radius:100px;font-size:11px;font-weight:700}.kw-1{background:#dff4ee;border-color:#c2e8dc}.kw-2{background:#ffeadc;border-color:#f8d2bb}.kw-3{background:#f4e7fb;border-color:#e8d4f5}
.atlas-hero-metrics{display:flex;align-items:center;gap:18px;margin-top:27px}.atlas-hero-metrics div{display:flex;flex-direction:column;gap:1px}.atlas-hero-metrics b{font-family:"Manrope",sans-serif;font-size:23px;line-height:1}.atlas-hero-metrics span{font-size:9px;letter-spacing:.12em;font-weight:800;color:#7c7c93}.atlas-hero-metrics i{width:1px;height:30px;background:#c7c1e7}
.atlas-hero-graphic{min-height:225px;position:relative;z-index:1;display:grid;place-items:center}.atlas-hero-graphic svg{width:min(100%,310px);height:auto;overflow:visible;filter:drop-shadow(0 12px 14px #5f568b18)}.atlas-orbit-label{position:absolute;background:#fffefa;border:1px solid #ddd8f5;padding:7px 10px;border-radius:9px;font-size:9px;font-weight:900;letter-spacing:.14em;box-shadow:0 6px 20px #34305b0c}.label-a{top:18%;right:7%}.label-b{bottom:15%;left:6%}.label-c{bottom:18%;right:8%}
.atlas-dashboard,.atlas-compare,.atlas-recall{background:#fffefa;border:1px solid #e9e4db;border-radius:24px;padding:24px}
.atlas-dash-title{display:flex;align-items:baseline;justify-content:space-between;gap:15px}.atlas-dash-title>span{font-size:10px;letter-spacing:.16em;color:#7165d9;font-weight:900}.atlas-dash-title h2,.atlas-section-title h2{font-family:"Manrope",sans-serif;font-size:23px;letter-spacing:-.045em;margin:5px 0 20px}
.atlas-map{display:flex;align-items:stretch;gap:8px;overflow-x:auto;padding:4px 0 13px}.atlas-map-node{flex:1;min-width:110px;display:flex;flex-direction:column;gap:12px;background:#f4f1eb;border:1px solid #e8e3d9;border-radius:15px;padding:14px}.atlas-map-node span{width:27px;height:27px;display:grid;place-items:center;background:#202743;color:#ffad83;border-radius:9px;font-size:10px;font-weight:900}.atlas-map-node strong{font-size:12px;line-height:1.3}.atlas-map-arrow{display:grid;place-items:center;color:#a49bd9;font-size:16px;align-self:center}
.atlas-big-idea{display:flex;gap:15px;align-items:flex-start;margin-top:12px;padding:18px;border-radius:17px;background:#202743;color:#fff}.atlas-big-icon{width:36px;height:36px;flex:0 0 auto;display:grid;place-items:center;background:#ff9c6c;color:#202743;border-radius:12px;font-size:22px}.atlas-big-idea small,.atlas-video-info small{display:block;font-size:9px;font-weight:900;letter-spacing:.15em;color:#ffb28c;margin-bottom:5px}.atlas-big-idea strong{font-size:16px;display:block}.atlas-core-chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:10px}.atlas-core-chips span{font-size:11px;color:#d8d9e5;background:#ffffff12;border:1px solid #ffffff16;padding:8px 10px;border-radius:10px;max-width:100%}
.atlas-section-title{display:flex;align-items:end;justify-content:space-between;gap:12px}.atlas-section-title h2{margin-bottom:0}.atlas-count{font-size:9px;font-weight:900;letter-spacing:.12em;color:#8a8b9b;border:1px solid #e6e1d7;background:#fffefa;padding:7px 10px;border-radius:100px;white-space:nowrap}
.atlas-concept-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}
.atlas-concept{min-width:0;padding:21px;background:#fffefa;border:1px solid #e9e4db;border-radius:22px;position:relative;overflow:hidden;box-shadow:0 5px 20px #29304b04}
.atlas-concept:before{content:"";position:absolute;inset:0 auto 0 0;width:4px;background:#ff9c6c}.atlas-concept:nth-child(4n+2):before{background:#62c9b6}.atlas-concept:nth-child(4n+3):before{background:#a99bf3}.atlas-concept:nth-child(4n+4):before{background:#e6bd5c}
.atlas-concept-top{display:flex;align-items:center;justify-content:space-between}.atlas-number{font-family:"Manrope",sans-serif;font-size:29px;font-weight:800;color:#e6e1f6;line-height:1}.atlas-tag{font-size:8px;font-weight:900;letter-spacing:.13em;color:#7165d9;background:#f0edff;border-radius:7px;padding:7px 8px}
.atlas-concept h3{font-family:"Manrope",sans-serif;font-size:18px;line-height:1.25;letter-spacing:-.03em;margin:15px 0}
.atlas-tiles{display:grid;gap:8px}.atlas-tile{display:grid;grid-template-columns:24px 1fr;gap:9px;align-items:start;background:#f7f5f0;border:1px solid #eeebe4;border-radius:12px;padding:11px;font-size:12px;line-height:1.5;color:#4f566c}.atlas-tile-index{width:22px;height:22px;display:grid;place-items:center;background:#fffefa;border:1px solid #e6e1d7;border-radius:7px;font-size:9px;font-weight:900;color:#7165d9}
.atlas-equation{font-family:"Manrope",sans-serif;font-weight:800;font-size:18px;line-height:1.45;text-align:center;padding:16px 12px;margin-top:11px;background:#e8f6f1;border:1px solid #cfece1;color:#246b61;border-radius:14px;overflow-wrap:anywhere}
.atlas-takeaway{display:flex;align-items:flex-start;gap:9px;border-top:1px dashed #e2ddd4;margin-top:14px;padding-top:13px;color:#6c7084;font-size:11px;line-height:1.5}.atlas-takeaway span{font-size:16px;color:#ff9368}.atlas-takeaway strong{font-weight:600}
.atlas-compare{padding:24px}.atlas-compare-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin-top:18px}.atlas-compare-card{padding:20px;border-radius:18px;border:1px solid #e9e4db;background:#f8f6f1}.compare-example{background:#e6f5ef;border-color:#d2eae0}.compare-exam{background:#fff0e6;border-color:#f7dcc9}.atlas-card-symbol{font-size:26px;font-weight:900;margin-bottom:10px;color:#7165d9}.compare-exam .atlas-card-symbol{color:#d97745}.atlas-compare-card>small{font-size:9px;letter-spacing:.15em;font-weight:900;color:#74788b}.atlas-sentence-stack{display:grid;gap:9px;margin-top:13px}.atlas-sentence-stack>div{display:grid;grid-template-columns:24px 1fr;gap:8px;font-size:12px;line-height:1.5;color:#454d64}.atlas-sentence-stack span{font-size:9px;font-weight:900;color:#7165d9}
.atlas-recall{padding:24px}.atlas-recall-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin-top:18px}.atlas-recall-card{background:#f7f5f0;border:1px solid #e9e4db;border-radius:18px;padding:17px;min-width:0}.atlas-recall-number{font-family:"Manrope",sans-serif;font-size:28px;color:#c8c1ef;font-weight:900;display:block}.atlas-recall-card small{font-size:9px;font-weight:900;letter-spacing:.14em;color:#7165d9}.atlas-recall-card h3{font-size:14px;line-height:1.4;min-height:58px;margin:10px 0 16px}.atlas-reveal{background:#202743;color:#fff;border:0;border-radius:10px;padding:10px 12px;font-size:11px;font-weight:800}.atlas-answer{margin-top:13px;padding:12px;background:#e6f5ef;border:1px solid #d0e9df;border-radius:12px;color:#35645b;font-size:12px;line-height:1.5}
.atlas-video{display:grid;grid-template-columns:90px 1fr 48px;gap:18px;align-items:center;background:#202743;color:#fff;border-radius:24px;padding:20px 24px;overflow:hidden;position:relative}.atlas-video:after{content:"";position:absolute;width:200px;height:200px;border:1px solid #ffffff12;border-radius:50%;right:8%;top:-70%;box-shadow:0 0 0 30px #ffffff06,0 0 0 60px #ffffff04}.atlas-video-art{height:78px;border-radius:17px;background:linear-gradient(135deg,#ff9c6c,#a99bf3);display:grid;place-items:center;position:relative;overflow:hidden}.atlas-video-art>span{display:grid;place-items:center;width:37px;height:37px;border-radius:50%;background:#202743;color:#fff;font-size:15px;z-index:1;padding-left:3px}.video-rings{position:absolute;width:110px;height:110px;border:1px solid #ffffff6b;border-radius:50%;box-shadow:0 0 0 13px #ffffff17}.atlas-video-info{position:relative;z-index:1}.atlas-video-info h2{font-family:"Manrope",sans-serif;font-size:18px;line-height:1.3;margin:5px 0 12px;letter-spacing:-.025em}.atlas-video-meta{display:flex;gap:7px;flex-wrap:wrap}.atlas-video-meta span{font-size:8px;letter-spacing:.12em;font-weight:900;padding:6px 8px;border-radius:7px;background:#ffffff12;color:#d4d7e5}.atlas-video-button{width:43px;height:43px;display:grid;place-items:center;background:#ff9c6c;color:#202743;border-radius:13px;font-size:21px;position:relative;z-index:1}
@media(max-width:1050px){.atlas-hero{grid-template-columns:1fr .6fr;padding:28px}.atlas-hero-graphic{min-height:190px}.atlas-concept-grid{grid-template-columns:1fr}.atlas-recall-grid{grid-template-columns:1fr 1fr}}
@media(max-width:700px){.content-wrap{padding:18px 14px}.hero{border-radius:22px}.hero-copy{padding:30px 23px}.hero-visual{min-height:270px}.atlas-hero{grid-template-columns:1fr;padding:23px;gap:0}.atlas-hero h1{font-size:31px}.atlas-hero-graphic{min-height:200px}.atlas-dashboard,.atlas-compare,.atlas-recall{padding:17px}.atlas-map{flex-wrap:nowrap}.atlas-map-arrow{min-width:12px}.atlas-compare-grid,.atlas-recall-grid{grid-template-columns:1fr}.atlas-video{grid-template-columns:62px 1fr 40px;gap:12px;padding:15px}.atlas-video-art{height:62px}.atlas-video-info h2{font-size:14px}.atlas-toolbar{gap:8px}.atlas-level{font-size:8px}.atlas-hero-metrics{gap:12px}.atlas-hero-metrics b{font-size:19px}.atlas-recall-card h3{min-height:0}}
@media print{.sidebar,.topbar,.atlas-toolbar-actions,.atlas-video,.atlas-reveal{display:none!important}.main-area{margin:0}.content-wrap{padding:0}.atlas-hero,.atlas-dashboard,.atlas-concept,.atlas-compare,.atlas-recall{break-inside:avoid;box-shadow:none}.atlas-concept-grid{grid-template-columns:1fr 1fr}}

.atlas-table-wrap{overflow-x:auto;border:1px solid #eeebe4;border-radius:13px;background:#f7f5f0}
.atlas-mini-table{width:100%;border-collapse:separate;border-spacing:0;font-size:12px;line-height:1.5;color:#4f566c}
.atlas-mini-table tr+tr th,.atlas-mini-table tr+tr td{border-top:1px solid #e8e3d9}
.atlas-mini-table th{width:43px;vertical-align:top;text-align:center;padding:12px 7px;color:#7165d9;font-size:9px;letter-spacing:.08em;background:#f0edff;font-weight:900}
.atlas-mini-table td{padding:12px 13px;vertical-align:top}
.atlas-mini-table tr:nth-child(even) td{background:#fffefa}
.atlas-concept h3{margin:13px 0}


/* Structural refresh: compact horizontal navigation and spacious learning canvas */
@media(min-width:1101px){
  .sidebar{position:sticky;inset:0 0 auto;width:100%;height:auto;min-height:76px;flex-direction:row;align-items:center;gap:24px;padding:12px 28px;overflow:hidden;border-bottom:1px solid #343c59;border-right:0;box-shadow:0 8px 26px #20274312}
  .brand{flex:0 0 auto;padding:0;gap:9px}
  .brand-mark{width:34px;height:34px;font-size:21px}
  .brand-copy strong{font-size:15px}
  .brand-copy small{font-size:8px}
  .sidebar-label,.sidebar-bottom{display:none}
  .side-nav{display:flex;align-items:center;gap:5px;flex:1;min-width:0;overflow-x:auto;scrollbar-width:thin;padding:2px 0}
  .nav-link{flex:0 0 auto;width:auto;min-height:42px;padding:0 12px;white-space:nowrap;font-size:11px;gap:7px}
  .nav-icon{font-size:14px}
  .nav-count{font-size:9px}
  .main-area{margin-left:0}
  .topbar{position:sticky;top:0;z-index:8}
  .content-wrap{max-width:1600px;margin:0 auto}
}
@media(max-width:1100px){
  .sidebar{background:#202743}
  .main-area{margin-left:0}
}

.atlas-table-wrap{overflow-x:auto;border:1px solid #eeebe4;border-radius:13px;background:#f7f5f0}
.atlas-mini-table{width:100%;border-collapse:separate;border-spacing:0;font-size:12px;line-height:1.5;color:#4f566c}
.atlas-mini-table tr+tr th,.atlas-mini-table tr+tr td{border-top:1px solid #e8e3d9}
.atlas-mini-table th{width:43px;vertical-align:top;text-align:center;padding:12px 7px;color:#7165d9;font-size:9px;letter-spacing:.08em;background:#f0edff;font-weight:900}
.atlas-mini-table td{padding:12px 13px;vertical-align:top}
.atlas-mini-table tr:nth-child(even) td{background:#fffefa}
.atlas-concept h3{margin:13px 0}


/* Visual lab sidebar and diagram-first note system */
.sidebar{width:264px;background:#171c31;border-right:1px solid #343955;padding:22px 15px 16px;box-shadow:9px 0 34px #15192c14}
.brand{padding:4px 8px 28px;gap:12px}
.brand-mark{width:43px;height:43px;border-radius:15px;background:linear-gradient(145deg,#d7f36c,#93dfb9);color:#1c2c38;font-size:27px;box-shadow:0 8px 25px #d7f36c21}
.brand-mark span{color:#ff936c}.brand-copy strong{font-size:20px;letter-spacing:-.9px}.brand-copy small{font-size:8px;color:#9ca8c9;letter-spacing:1.55px}
.sidebar-label{padding:0 13px 10px;color:#777fa5;font-size:9px;letter-spacing:2px}
.side-nav{gap:6px}.nav-link{position:relative;display:flex;align-items:center;gap:12px;min-height:47px;padding:8px 11px;border:1px solid transparent;border-radius:13px;background:transparent;color:#aeb7d1;font-size:12px;overflow:hidden}
.nav-link:before{content:"";position:absolute;left:0;top:9px;bottom:9px;width:3px;border-radius:0 4px 4px 0;background:transparent}
.nav-link:hover{background:#252b46;border-color:#343b5b;color:#fff}
.nav-link.active{background:linear-gradient(105deg,#d8f36c,#b8e6a3);border-color:#d8f36c;color:#20283b;box-shadow:0 8px 20px #d8f36c14;font-weight:800}
.nav-link.active:before{background:#20283b}
.nav-icon{display:grid;place-items:center;width:29px;height:29px;flex:0 0 29px;border-radius:9px;background:#272d49;color:#c5c9e4;font-size:16px}
.nav-link.active .nav-icon{background:#f5ffd5;color:#263342}.nav-caption{flex:1}
.nav-count{margin-left:auto;background:#343b5c;color:#e5e8ff;border-radius:7px;padding:3px 7px;font-size:9px}
.nav-link.active .nav-count{background:#26364a;color:#e6f5c1}.live-dot{margin-left:auto;background:#f4a16f;box-shadow:0 0 0 4px #f4a16f1f}
.sidebar-bottom{margin-top:auto}.sidebar-molecule-card{padding:13px;border:1px solid #3a405f;border-radius:18px;background:linear-gradient(145deg,#242a46,#1d2239);overflow:hidden}
.mini-periodic-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:5px}
.mini-periodic-grid span,.mini-periodic-grid i{height:28px;border-radius:7px;display:grid;place-items:center;font-size:10px;font-style:normal;font-weight:900}
.mini-periodic-grid span{background:#333b5c;color:#dce5ff;border:1px solid #495174}
.mini-periodic-grid span:nth-of-type(3n+1){background:#d8f36c;color:#263342;border-color:#d8f36c}
.mini-periodic-grid span:nth-of-type(3n+2){background:#83dec6;color:#203847;border-color:#83dec6}
.mini-periodic-grid i{background:#ffffff04;border:1px dashed #3a4261}
.sidebar-card-caption{display:flex;align-items:center;gap:8px;margin-top:14px;font-size:8px;letter-spacing:.12em;color:#aab4d3}
.sidebar-card-caption span{display:grid;place-items:center;width:24px;height:24px;border-radius:7px;background:#343b5c;color:#d8f36c;font-size:9px}
.sidebar-card-caption b{font-weight:900}
.sidebar-practice-link{display:flex;align-items:center;justify-content:space-between;width:100%;border:0;border-top:1px solid #3a405f;margin-top:12px;padding:12px 0 1px;background:transparent;color:#d8f36c;font-size:9px;font-weight:900;letter-spacing:.14em}
.sidebar-foot{font-size:8px;letter-spacing:.09em;padding:14px 4px 0;color:#7f89aa}
@media(min-width:1101px){.sidebar{position:fixed;inset:0 auto 0 0;width:264px;height:100vh;flex-direction:column;align-items:stretch;gap:0;padding:22px 15px 16px;overflow-y:auto;border-bottom:0;border-right:1px solid #343955}.sidebar-label,.sidebar-bottom{display:block}.side-nav{display:grid;overflow:visible}.nav-link{width:100%;min-height:47px;flex:initial}.main-area{margin-left:264px}.topbar{top:0}.content-wrap{max-width:1560px;padding:32px 38px 24px}}
@media(max-width:1100px){.sidebar{width:264px;position:fixed;inset:0 auto 0 0;height:100vh;transform:translateX(-105%);transition:transform .22s;z-index:20;overflow-y:auto}.sidebar.open{transform:translateX(0);box-shadow:20px 0 60px #11182d60}.main-area{margin-left:0}.mobile-menu{display:block}}
.atlas-flow-board{display:flex;flex-direction:column;align-items:stretch;gap:0}
.atlas-flow-node{display:grid;grid-template-columns:31px minmax(0,1fr);gap:10px;align-items:center;padding:12px 13px;border:1px solid #e5e2ed;border-radius:13px;background:#f7f6fb;color:#454b63;font-size:12px;line-height:1.5;position:relative}
.atlas-flow-node>span{width:27px;height:27px;border-radius:9px;display:grid;place-items:center;background:#e8e4fa;color:#6558c7;font-size:9px;font-weight:900}
.atlas-flow-node.node-1{background:#edf8f4;border-color:#d8eee5}.atlas-flow-node.node-1>span{background:#d0eee2;color:#247b69}
.atlas-flow-node.node-2{background:#fff2e9;border-color:#f5dfd0}.atlas-flow-node.node-2>span{background:#ffe0ca;color:#b96d43}
.atlas-flow-node.node-3{background:#eef3ff;border-color:#dce5fb}.atlas-flow-node.node-3>span{background:#dce6ff;color:#4b64bd}
.atlas-flow-connector{height:24px;display:grid;place-items:center;color:#8b83c9;font-size:15px;font-weight:900;line-height:1}
.atlas-concept{border-radius:24px;padding:23px}.atlas-concept h3{font-size:19px;margin:13px 0 16px}
.atlas-takeaway{background:#f4f1ff;border:1px solid #e5defc;border-radius:12px;padding:11px 12px;margin-top:13px}
.atlas-takeaway strong{color:#4e4c70;font-size:11px}
.atlas-map{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));align-items:stretch;gap:9px;overflow:visible;padding:6px 0 15px}
.atlas-map-node{min-width:0;position:relative;background:#f4f1ff;border-color:#e3def8}
.atlas-map-node:after{content:"↗";position:absolute;right:10px;top:12px;color:#9588d9;font-size:12px}
.atlas-map-node.map-node-1{background:#e9f7f1;border-color:#d4ede2}.atlas-map-node.map-node-2{background:#fff0e5;border-color:#f6decd}.atlas-map-node.map-node-3{background:#edf2ff;border-color:#dbe4fc}
.atlas-map-arrow{display:none}
@media(max-width:780px){.atlas-map{grid-template-columns:repeat(2,minmax(0,1fr))}.atlas-flow-node{font-size:11px;padding:10px}.atlas-concept{padding:17px}}
@media(max-width:420px){.atlas-map{grid-template-columns:1fr 1fr}.atlas-hero-metrics{gap:8px}.atlas-hero-metrics span{font-size:8px}}


/* Two-year teaching sequence labels */
.course-sequence-label{
  display:block;
  margin:0 0 5px;
  color:#78d9b2;
  font-size:9px;
  font-weight:800;
  letter-spacing:.075em;
  line-height:1.45;
  text-transform:uppercase;
}
.topic-button .course-sequence-label{color:#3d9b7b;}
.topic-button.active .course-sequence-label{color:#a6f0d1;}


/* Two-year IB Chemistry roadmap */
.roadmap-hero{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(240px,.7fr);gap:28px;align-items:center;padding:clamp(24px,4vw,48px);border-radius:28px;background:linear-gradient(120deg,#0b1728 0%,#102d3b 56%,#183d43 100%);color:#f3f7fb;position:relative;overflow:hidden;margin-bottom:22px}
.roadmap-hero-copy{position:relative;z-index:2}.roadmap-hero h1{font-size:clamp(34px,4vw,55px);line-height:1.03;letter-spacing:-.055em;margin:13px 0 16px}.roadmap-hero h1 span{color:#73e0bb}.roadmap-hero p{max-width:620px;color:#b8c8d6;line-height:1.7;margin:0}.roadmap-stats{display:flex;align-items:center;gap:22px;margin-top:27px}.roadmap-stats div{display:grid;gap:4px}.roadmap-stats strong{font-size:28px;line-height:1;color:#f7fbff}.roadmap-stats span{font-size:9px;letter-spacing:.12em;color:#a7bac7;font-weight:800}.roadmap-stats i{height:34px;width:1px;background:#45616c}
.roadmap-visual{min-height:230px;position:relative;display:grid;place-items:center}.roadmap-core{width:110px;height:110px;border-radius:50%;display:grid;place-content:center;text-align:center;background:linear-gradient(135deg,#70e0b9,#7fb8ff);color:#09202b;font-size:26px;font-weight:900;box-shadow:0 0 55px #6ad7b744;z-index:2;line-height:1.05}.roadmap-core b{font-size:12px;letter-spacing:.15em}.roadmap-orbit{position:absolute;border:1px solid #7cdac66b;border-radius:50%;transform:rotate(-28deg)}.orbit-a{width:245px;height:115px}.orbit-b{width:210px;height:185px;transform:rotate(48deg);border-color:#a6c8ff66}.orbit-tag{position:absolute;padding:7px 10px;border-radius:9px;font-size:9px;font-weight:900;letter-spacing:.1em;background:#0b1d2a;border:1px solid #45636b;color:#bcefe0}.tag-structure{top:15px;left:10px}.tag-reactivity{right:0;bottom:20px;color:#c7d7ff}
.roadmap-principle{display:flex;align-items:center;gap:18px;padding:18px 22px;background:#eaf8f2;border:1px solid #cceee0;border-radius:16px;margin-bottom:26px}.roadmap-principle>span:first-child{font-size:10px;font-weight:900;letter-spacing:.13em;color:#268565;white-space:nowrap}.roadmap-principle strong{font-size:clamp(14px,1.6vw,18px);color:#163c35;flex:1}.principle-arrow{font-size:25px;color:#2e9c7b}
.course-roadmap{display:grid;gap:26px}.roadmap-year{border:1px solid var(--line,#e1e7e8);border-radius:23px;overflow:hidden;background:var(--panel,#fff);box-shadow:0 10px 35px #0a27310b}.roadmap-year-head{display:grid;grid-template-columns:60px 1fr auto;align-items:center;gap:18px;padding:25px 28px;background:linear-gradient(110deg,#effaf5,#f6fbfa);border-bottom:1px solid #dcefe7}.year-2 .roadmap-year-head{background:linear-gradient(110deg,#f0f3ff,#f8f9ff);border-color:#e0e5fa}.year-number{font-size:35px;font-weight:900;letter-spacing:-.08em;color:#268b6b}.year-2 .year-number{color:#6177d6}.roadmap-year-head>div:nth-child(2)>span{font-size:9px;font-weight:900;letter-spacing:.13em;color:#32886d}.year-2 .roadmap-year-head>div:nth-child(2)>span{color:#6276ca}.roadmap-year-head h2{font-size:25px;letter-spacing:-.04em;margin:3px 0 5px}.roadmap-year-head p{font-size:13px;color:var(--muted,#667580);margin:0;line-height:1.5}.year-topic-count{font-size:30px;font-weight:900;text-align:right;color:#287e64}.year-2 .year-topic-count{color:#6377ce}.year-topic-count small{display:block;font-size:9px;letter-spacing:.1em;color:var(--muted,#667580)}
.roadmap-units{padding:8px 28px 22px}.roadmap-unit{display:grid;grid-template-columns:38px minmax(0,1fr);gap:15px}.unit-rail{display:flex;align-items:center;flex-direction:column;padding-top:24px}.unit-rail span{display:grid;place-items:center;width:32px;height:32px;border-radius:11px;background:#e3f7ef;color:#267d62;font-size:11px;font-weight:900}.year-2 .unit-rail span{background:#e9edff;color:#596fc3}.unit-rail i{width:1px;flex:1;min-height:30px;background:#dbe8e4}.roadmap-unit:last-child .unit-rail i{background:transparent}.roadmap-unit-body{padding:22px 0 24px;border-bottom:1px solid var(--line,#e7ebec)}.roadmap-unit:last-child .roadmap-unit-body{border-bottom:0}.roadmap-unit-body>header{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:13px}.roadmap-unit-body>header small{font-size:9px;letter-spacing:.12em;font-weight:900;color:#368c70}.year-2 .roadmap-unit-body>header small{color:#6479cf}.roadmap-unit-body h3{font-size:19px;letter-spacing:-.03em;margin:4px 0 0}.unit-topic-count{font-size:9px;font-weight:900;letter-spacing:.08em;color:var(--muted,#667580);white-space:nowrap}
.roadmap-topic-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}.roadmap-topic{display:grid;grid-template-columns:58px minmax(0,1fr) 18px;align-items:center;gap:11px;text-align:left;padding:13px 14px;border:1px solid var(--line,#e1e7e8);border-radius:13px;background:var(--surface,#fbfcfc);color:var(--text,#192b35);cursor:pointer;min-height:62px;transition:transform .16s,border-color .16s,background .16s}.roadmap-topic:hover{transform:translateY(-2px);border-color:#6bc6a7;background:#f1fbf6}.year-2 .roadmap-topic:hover{border-color:#9aa9ef;background:#f5f6ff}.roadmap-topic-code{display:grid;place-items:center;padding:7px 4px;border-radius:8px;background:#dff5eb;color:#287f63;font-size:11px;font-weight:900;white-space:nowrap}.year-2 .roadmap-topic-code{background:#e6eaff;color:#596dc0}.roadmap-topic-name{font-size:12px;font-weight:700;line-height:1.45}.roadmap-topic-arrow{font-size:15px;color:#6a9f8c}
.course-tools-strip{display:flex;align-items:center;gap:16px;flex-wrap:wrap;padding:22px 24px;margin-top:22px;border-radius:18px;background:#101f2c;color:#f4f8fa}.tools-strip-icon{display:grid;place-items:center;width:44px;height:44px;border-radius:13px;background:#244d4a;color:#80e1c0;font-size:26px}.course-tools-strip>div:nth-child(2){flex:1;min-width:180px}.course-tools-strip small{font-size:9px;letter-spacing:.12em;font-weight:900;color:#7cdbb9}.course-tools-strip h3{margin:4px 0;font-size:16px}.course-tools-strip p{font-size:12px;color:#b6c6d0;margin:0}.tools-topic{padding:10px 12px;border:1px solid #36505b;border-radius:10px;background:#192d3b;color:#e7f5f2;font-size:11px;font-weight:700;cursor:pointer}.tools-topic span{color:#83e0c0;margin-left:6px}.roadmap-source{font-size:11px;color:var(--muted,#667580);padding:18px 4px 0;line-height:1.8}.roadmap-source a{color:#288b6d;text-decoration:none;font-weight:800}.roadmap-source a:hover{text-decoration:underline}
.atlas-video-embed{display:block;padding:22px;border:1px solid var(--line,#e2e8e8);border-radius:20px;background:var(--panel,#fff);margin:25px 0}.atlas-video-heading{margin-bottom:14px}.atlas-video-heading>small{font-size:10px;letter-spacing:.12em;font-weight:900;color:#348a70}.atlas-video-heading h2{font-size:20px;margin:7px 0}.atlas-video-heading>span{font-size:9px;font-weight:800;letter-spacing:.12em;color:var(--muted,#667580)}.atlas-video-frame{aspect-ratio:16/9;width:100%;max-height:600px;border-radius:14px;overflow:hidden;background:#0a1119}.atlas-video-frame iframe{width:100%;height:100%;border:0;display:block}.atlas-video-open{display:inline-block;margin-top:12px;color:#2e8b6c;font-size:12px;font-weight:800;text-decoration:none}
@media(max-width:800px){.roadmap-hero{grid-template-columns:1fr}.roadmap-visual{min-height:190px;max-width:360px;width:100%;margin:auto}.roadmap-topic-list{grid-template-columns:1fr}.roadmap-year-head{padding:21px 18px;grid-template-columns:48px 1fr auto;gap:12px}.roadmap-units{padding:4px 16px 15px}.roadmap-principle{align-items:flex-start;flex-wrap:wrap;gap:9px 14px}.roadmap-principle strong{flex-basis:calc(100% - 30px)}.roadmap-principle>span:first-child{width:100%}.roadmap-stats{gap:13px}.roadmap-stats strong{font-size:23px}.roadmap-stats span{font-size:8px}.course-tools-strip{align-items:flex-start}.tools-topic{width:100%;text-align:left}.roadmap-hero{padding:26px 22px}}


/* GchemIB sidebar redesign — navigation grouped by learning task */
.sidebar{width:278px;padding:17px 14px 13px;background:#0b1422;border-right:1px solid #253247;color:#edf4f8;display:flex;flex-direction:column;gap:0;overflow-x:hidden;scrollbar-width:thin;scrollbar-color:#33445b transparent}
.sidebar:before{content:"";position:absolute;top:-100px;left:-100px;width:270px;height:270px;border-radius:50%;background:radial-gradient(circle,#1b665d25,transparent 70%);pointer-events:none}
.sidebar-topline{height:25px;display:flex;align-items:center;gap:7px;padding:0 8px;color:#7f95a9;font-size:8px;letter-spacing:.105em;font-weight:800;white-space:nowrap;position:relative}
.sidebar-live-dot{width:6px;height:6px;border-radius:50%;background:#6ee7b7;box-shadow:0 0 0 3px #6ee7b71a}
.sidebar-version{margin-left:auto;padding:3px 6px;border:1px solid #33445a;border-radius:5px;color:#b9cad7;font-size:8px}
.sidebar .brand{display:flex;align-items:center;gap:10px;position:relative;padding:14px 8px 17px;margin:0;text-decoration:none;border-bottom:1px solid #253247}
.sidebar .brand-mark{display:grid;place-items:center;width:42px;height:42px;flex:0 0 42px;border-radius:14px;background:linear-gradient(145deg,#baf3db,#68c7ac);color:#102d31;box-shadow:0 8px 22px #54c5a21c}
.sidebar .brand-mark svg{width:31px;height:31px}
.sidebar .brand-copy{display:flex;flex-direction:column;gap:3px;min-width:0}
.sidebar .brand-copy strong{font-size:21px;line-height:1;letter-spacing:-.065em;color:#f2f7fb}
.sidebar .brand-copy strong span{color:#77d9b6}
.sidebar .brand-copy small{font-size:7px;letter-spacing:.12em;color:#8fa5b6;font-weight:800}
.sidebar .brand-arrow{margin-left:auto;color:#6e8798;font-size:15px;opacity:0;transition:opacity .18s}
.sidebar .brand:hover .brand-arrow{opacity:1}
.sidebar-course-chip{display:flex;align-items:center;gap:10px;margin:14px 3px 17px;padding:11px 10px;border:1px solid #26384b;background:linear-gradient(120deg,#142537,#12212d);border-radius:13px;position:relative}
.course-chip-symbol{display:grid;place-items:center;width:34px;height:34px;flex:0 0 34px;border-radius:10px;background:#244d49;color:#9ce9cd;font-size:20px}
.sidebar-course-chip>span:last-child{display:flex;flex-direction:column;gap:4px;min-width:0}
.sidebar-course-chip b{font-size:10px;letter-spacing:.04em;color:#e6f3f3}
.sidebar-course-chip small{font-size:7px;letter-spacing:.035em;color:#8fa8b9;white-space:nowrap}
.sidebar .side-nav{display:flex;flex-direction:column;gap:4px;overflow:visible;flex:1}
.sidebar .nav-group-label{padding:0 11px 5px;color:#72899e;font-size:8px;letter-spacing:.16em;font-weight:900}
.sidebar .nav-group-spaced{margin-top:17px}
.sidebar .nav-link{position:relative;display:flex;align-items:center;gap:10px;width:100%;min-height:48px;padding:7px 9px;border:1px solid transparent;border-radius:12px;background:transparent;color:#a8bac8;text-align:left;overflow:hidden;transition:background .17s,border-color .17s,color .17s,transform .17s}
.sidebar .nav-link:before{content:"";position:absolute;left:0;top:10px;bottom:10px;width:2px;border-radius:0 3px 3px 0;background:transparent}
.sidebar .nav-link:hover{background:#152637;border-color:#263c4c;color:#f1f8f9;transform:translateX(1px)}
.sidebar .nav-link.active{background:linear-gradient(105deg,#183c3c,#163331);border-color:#28544c;color:#f4fffb;box-shadow:inset 0 0 0 1px #6ee7b70b}
.sidebar .nav-link.active:before{background:#7ee4bd}
.sidebar .nav-icon{display:grid;place-items:center;width:31px;height:31px;flex:0 0 31px;border-radius:9px;background:#18283a;color:#b4c8d4;font-size:17px;font-weight:700}
.sidebar .nav-link.active .nav-icon{background:#28534c;color:#a5f1d1}
.sidebar .nav-icon-course{font-size:9px;letter-spacing:-.04em;font-weight:900}
.sidebar .nav-icon-ai{color:#c2b4ff}
.sidebar .nav-copy{display:flex;flex-direction:column;gap:3px;min-width:0;flex:1}
.sidebar .nav-copy b{font-size:11px;line-height:1.15;font-weight:750;color:inherit}
.sidebar .nav-copy small{font-size:9px;line-height:1.2;color:#71889b;white-space:nowrap}
.sidebar .nav-link.active .nav-copy small{color:#8dbcae}
.sidebar .nav-count{display:grid;place-items:center;min-width:22px;height:20px;padding:0 5px;border-radius:7px;background:#223d43;color:#9fe7c9;font-size:9px;font-weight:900}
.sidebar .nav-active-arrow{font-size:13px;color:#8be4bf}
.sidebar .nav-ai-dot{width:6px;height:6px;flex:0 0 6px;border-radius:50%;background:#a89aff;box-shadow:0 0 0 4px #a89aff14}
.sidebar .sidebar-bottom{display:block;margin-top:19px}
.sidebar-journey-card{padding:13px 12px 11px;border:1px solid #27384a;border-radius:15px;background:linear-gradient(145deg,#132637,#101e2b);position:relative;overflow:hidden}
.sidebar-journey-card:after{content:"";position:absolute;width:100px;height:100px;right:-50px;top:-55px;border-radius:50%;background:#71dfb40d;pointer-events:none}
.journey-card-head{display:flex;justify-content:space-between;align-items:center;gap:8px;font-size:8px;letter-spacing:.1em;color:#a6bac8;font-weight:900}
.journey-spark{color:#8fe4c2;font-size:13px}
.journey-track{display:flex;align-items:center;margin:15px 7px 8px}
.journey-stop{width:25px;height:25px;display:grid;place-items:center;flex:0 0 25px;border-radius:8px;background:#254940;border:1px solid #386e5b;color:#a1edce;font-size:8px;font-weight:900}
.journey-stop-two{background:#253950;border-color:#40577b;color:#b7caff}
.journey-stop-three{background:#302b4b;border-color:#514879;color:#d0c4ff}
.journey-line{height:1px;flex:1;background:linear-gradient(90deg,#467765,#40526c)}
.journey-labels{display:grid;grid-template-columns:1fr 1fr 1fr;text-align:center}
.journey-labels span{display:flex;flex-direction:column;gap:3px}
.journey-labels b{font-size:9px;color:#e0edf3}
.journey-labels small{font-size:8px;color:#8097a9}
.sidebar .sidebar-journey-link{display:flex;align-items:center;justify-content:space-between;width:100%;margin-top:13px;padding:10px 9px;border:1px solid #335148;border-radius:9px;background:#1b3b38;color:#b2f1d7;font-size:8px;font-weight:900;letter-spacing:.09em;cursor:pointer;transition:background .18s}
.sidebar .sidebar-journey-link:hover{background:#245049}
.sidebar .sidebar-journey-link span{font-size:13px}
.sidebar .sidebar-foot{display:flex;align-items:center;gap:7px;margin:11px 4px 0;padding:9px 4px 0;border-top:1px solid #243345;color:#70899a;font-size:7px;font-weight:800;letter-spacing:.07em}
.sidebar .status-dot{width:6px;height:6px;flex:0 0 6px;border-radius:50%;background:#6ee7b7}
.sidebar-foot-version{margin-left:auto;color:#526a7e;font-variant-numeric:tabular-nums}
@media(max-width:1100px){.sidebar{width:278px;padding-top:17px}.sidebar.open{box-shadow:20px 0 60px #07111fb8}.sidebar .nav-link{min-height:49px}}
@media(max-height:760px){.sidebar{padding-top:10px;padding-bottom:8px}.sidebar-course-chip{margin-top:9px;margin-bottom:11px}.sidebar .nav-group-spaced{margin-top:9px}.sidebar .nav-link{min-height:43px}.sidebar .sidebar-bottom{margin-top:10px}.sidebar-journey-card{padding:10px 11px 8px}.journey-track{margin-top:10px}}

/* Keep the content grid aligned with the redesigned 278px sidebar */
@media(min-width:1101px){.main-area{margin-left:278px}}


/* Two-year IB Chemistry sequence: concise scope line for every unit */
.roadmap-focus{margin:0 0 13px;padding:11px 13px;border-radius:10px;background:#f4f8f7;color:#50646d;font-size:12px;line-height:1.65;border-left:3px solid #69c8a6}
.year-2 .roadmap-focus{background:#f5f6fc;border-left-color:#8798eb}
.roadmap-unit-body>header{align-items:flex-start}
.roadmap-unit-body>header>div{min-width:0}
.roadmap-unit-body>header .unit-topic-count{padding-top:6px}
@media(max-width:720px){.roadmap-topic-list{grid-template-columns:minmax(0,1fr)}.roadmap-focus{font-size:11.5px}.roadmap-unit-body>header h3{font-size:17px}}


/* Readability upgrade: larger typography across the whole study hub */
html{font-size:17px}
body{font-size:16px;line-height:1.65}
body p,body li,body td,body th,body label,body summary,
.hero-copy>p,.page-intro p,.feature-card p,.panel p,.card p,
.note-reader p,.note-reader li,.section-content p,.section-content li,
.study-concept-content p,.study-big-idea p,.atlas-dashboard p,.atlas-concept p,
.atlas-compare p,.atlas-recall p,.roadmap-focus,.course-tools-strip p{
  font-size:max(1.08em,14px)!important;
  line-height:1.7;
}
body button,body input,body select,body textarea{font-size:max(1.06em,13px)}
body small,.eyebrow,.section-kicker,.sidebar .nav-group-label,
.sidebar .nav-copy b,.sidebar .nav-copy small,
.sidebar-course-chip b,.sidebar-course-chip small,
.journey-card-head,.journey-labels b,.journey-labels small,
.sidebar .sidebar-journey-link,.sidebar .sidebar-foot,
.roadmap-topic-code,.unit-topic-count,.roadmap-unit-body>header small,
.note-section-label,.topic-button small,.card-bottom,
.study-topline,.study-video-copy,.study-practice-meta span,
.atlas-level,.atlas-big-idea small,.atlas-video-info small{
  font-size:max(1.1em,11px)!important;
}
.roadmap-topic-name{font-size:14px!important;line-height:1.55}
.roadmap-focus{font-size:14px!important}
.sidebar .nav-copy b{font-size:13px!important;line-height:1.25}
.sidebar .nav-copy small{font-size:11px!important;line-height:1.35;white-space:normal}
.sidebar .nav-group-label{font-size:10px!important}
.sidebar-course-chip b{font-size:12px!important}
.sidebar-course-chip small{font-size:9px!important;white-space:normal}
.journey-card-head{font-size:10px!important}
.journey-labels b{font-size:11px!important}
.journey-labels small{font-size:9px!important}
.sidebar .sidebar-journey-link{font-size:10px!important}
.sidebar .sidebar-foot{font-size:9px!important}
@media(max-width:720px){
  body{font-size:15.5px}
  body p,body li,body td,body th,.roadmap-focus{font-size:14px!important}
  .sidebar .nav-copy b{font-size:13px!important}
}

/* VISUAL TEXTBOOK UPGRADE — readable, illustrated study sheets */
#note-reader{max-width:1500px;margin-inline:auto}
.atlas-toolbar{padding:16px 22px!important}
.atlas-hero{grid-template-columns:minmax(0,1.45fr) minmax(240px,.75fr)!important;min-height:260px!important;padding:clamp(24px,3vw,42px)!important;border-radius:24px!important;background:linear-gradient(125deg,#eaf7ff 0%,#effcf8 58%,#f7f0ff 100%)!important;color:#14283d!important;border:1px solid #cde6ef!important;overflow:hidden}
.atlas-hero h1{font-size:clamp(32px,3.5vw,48px)!important;line-height:1.08!important;letter-spacing:-1.3px!important;color:#10263d!important;max-width:780px}
.atlas-kicker{font-size:12px!important;letter-spacing:1.4px!important;color:#176e79!important}
.atlas-keyword{font-size:13px!important;padding:7px 11px!important;border-radius:999px!important}
.atlas-hero-metrics{margin-top:25px!important;gap:18px!important}
.atlas-hero-metrics b{font-size:27px!important;color:#12344c!important}
.atlas-hero-metrics span{font-size:11px!important;color:#537087!important}
.atlas-hero-graphic{min-height:220px!important;background:radial-gradient(ellipse at center,#d6f6ef 0%,#e5f3ff 56%,transparent 72%)!important;border-radius:20px!important}
.atlas-dashboard,.atlas-concept,.atlas-compare,.atlas-recall,.atlas-video{border-radius:20px!important}
.atlas-dashboard{padding:clamp(18px,2vw,28px)!important;background:#f3f8ff!important;border:1px solid #d6e7f6!important;color:#17334b!important}
.atlas-dash-title h2,.atlas-section-title h2{font-size:clamp(22px,2vw,29px)!important;line-height:1.2!important;color:#142b43!important}
.atlas-dash-title>span,.atlas-section-title>div>span{font-size:12px!important;letter-spacing:1.3px!important}
.atlas-map{gap:10px!important;align-items:stretch!important}
.atlas-map-node{min-height:76px!important;padding:15px!important;border-radius:14px!important;background:#fff!important;border:1px solid #d6e6f4!important;box-shadow:0 4px 14px #18334d0b!important}
.atlas-map-node strong{font-size:15px!important;line-height:1.35!important;color:#183650!important}
.atlas-map-arrow{font-size:20px!important;color:#188b89!important}
.atlas-big-idea{padding:18px!important;border-radius:16px!important;background:#e1f7f0!important;color:#17394b!important}
.atlas-big-idea strong{font-size:18px!important;line-height:1.35!important;color:#123b4b!important}
.atlas-big-idea small{font-size:11px!important;letter-spacing:1.2px!important}
.atlas-core-chips{gap:8px!important}
.atlas-core-chips span{font-size:14px!important;line-height:1.55!important;padding:10px 12px!important;background:#fff!important;border:1px solid #cfe9e2!important;border-radius:12px!important;color:#24465b!important}
.atlas-section-title{margin:30px 0 15px!important;align-items:end!important}
.atlas-count{font-size:11px!important;padding:7px 10px!important;border-radius:999px!important;background:#e5f2ff!important;color:#275a7c!important}
.atlas-concept-grid{grid-template-columns:repeat(2,minmax(0,1fr))!important;gap:16px!important}
.atlas-concept{padding:clamp(18px,2vw,26px)!important;background:#fff!important;border:1px solid #d8e7f1!important;box-shadow:0 8px 25px #102b4210!important;color:#203a50!important;min-width:0}
.atlas-concept-top{margin-bottom:12px!important}
.atlas-number{width:38px!important;height:38px!important;font-size:16px!important;background:#12354b!important;color:#fff!important}
.atlas-tag{font-size:11px!important;letter-spacing:.9px!important;padding:6px 9px!important;border-radius:999px!important;background:#e4f7f4!important;color:#126f70!important}
.atlas-concept h3{font-size:clamp(20px,1.8vw,25px)!important;line-height:1.2!important;color:#142c43!important;margin:8px 0 15px!important}
.atlas-flow-board{gap:8px!important}
.atlas-flow-node{display:grid!important;grid-template-columns:30px minmax(0,1fr)!important;align-items:start!important;gap:10px!important;padding:13px 14px!important;border-radius:12px!important;background:#f2f7fc!important;border:1px solid #dce9f3!important;color:#203c52!important;font-size:15px!important;line-height:1.65!important}
.atlas-flow-node>span{display:grid!important;place-items:center!important;width:27px!important;height:27px!important;border-radius:8px!important;background:#dceeff!important;color:#235c82!important;font-size:12px!important;font-weight:800!important}
.atlas-flow-node.node-1{background:#effaf7!important;border-color:#d4eee5!important}.atlas-flow-node.node-1>span{background:#d3f3e8!important;color:#176e5a!important}
.atlas-flow-node.node-2{background:#fff8eb!important;border-color:#f3e5c7!important}.atlas-flow-node.node-2>span{background:#ffebc2!important;color:#8a5a11!important}
.atlas-flow-node.node-3{background:#f6f1ff!important;border-color:#e7dcff!important}.atlas-flow-node.node-3>span{background:#e7dcff!important;color:#6343a0!important}
.atlas-flow-connector{font-size:20px!important;line-height:1!important;color:#15968d!important;padding-left:15px!important}
.atlas-equation{font-size:clamp(17px,1.8vw,22px)!important;line-height:1.55!important;padding:16px!important;margin-top:12px!important;border-radius:13px!important;background:#edf5ff!important;border:1px solid #d1e4fa!important;color:#163d60!important;overflow-wrap:anywhere}
.atlas-takeaway{margin-top:13px!important;padding:13px 15px!important;border-radius:12px!important;background:#fff5da!important;border:1px solid #f3e1ae!important;color:#624817!important;display:flex!important;gap:10px!important;align-items:flex-start!important}
.atlas-takeaway strong{font-size:14px!important;line-height:1.6!important}
.atlas-compare,.atlas-recall{padding:clamp(18px,2vw,28px)!important;background:#f5f9fd!important;border:1px solid #dce9f4!important}
.atlas-compare-grid,.atlas-recall-grid{gap:14px!important}
.atlas-compare-card,.atlas-recall-card{padding:20px!important;border-radius:16px!important;background:#fff!important;border:1px solid #dce8f2!important;color:#20394e!important}
.atlas-compare-card small,.atlas-recall-card small{font-size:11px!important;letter-spacing:1px!important;color:#55738b!important}
.atlas-sentence-stack>div{font-size:15px!important;line-height:1.65!important;padding:11px 0!important;color:#20394e!important}
.atlas-sentence-stack>div span{font-size:12px!important;color:#17877f!important;margin-right:10px!important}
.atlas-recall-card h3{font-size:18px!important;line-height:1.45!important;color:#18334a!important}
.atlas-reveal{font-size:14px!important;padding:10px 13px!important;border-radius:10px!important}
.atlas-answer{margin-top:12px!important;padding:13px!important;background:#e9f8f2!important;border-radius:12px!important;font-size:15px!important;line-height:1.7!important;color:#174a40!important}
.atlas-video{display:grid!important;grid-template-columns:minmax(220px,.65fr) minmax(0,1.35fr)!important;gap:20px!important;align-items:center!important;padding:clamp(18px,2vw,28px)!important;background:#112b40!important;color:#f3f9ff!important}
.atlas-video-heading h2{font-size:clamp(22px,2vw,29px)!important;line-height:1.25!important;color:#fff!important}
.atlas-video-heading small,.atlas-video-heading span{font-size:11px!important;letter-spacing:1px!important}
.atlas-video-frame{min-height:250px!important;border-radius:15px!important;overflow:hidden!important}
.atlas-video-open{font-size:14px!important;color:#8ef0dc!important}
@media(max-width:850px){.atlas-concept-grid{grid-template-columns:1fr!important}.atlas-hero{grid-template-columns:1fr!important}.atlas-hero-graphic{max-height:230px!important}.atlas-video{grid-template-columns:1fr!important}.atlas-video-frame{min-height:220px!important}}
@media(max-width:520px){.atlas-hero{padding:22px!important}.atlas-hero h1{font-size:30px!important}.atlas-flow-node{font-size:14px!important;padding:11px!important}.atlas-core-chips span{font-size:13px!important}.atlas-map-node strong{font-size:13px!important}}

/* NEW NOTE LAYOUT: editorial chemistry textbook, replacing the old atlas-card look */
#note-reader{max-width:1480px;margin:0 auto;color:#1c3448}
.textbook-topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:18px 4px 22px;border-bottom:1px solid #dbe5ec;margin-bottom:22px}
.textbook-brand{display:flex;align-items:center;gap:11px}.textbook-brand-mark{display:grid;place-items:center;width:42px;height:42px;border-radius:13px;background:#14354a;color:#a5f0d9;font-size:22px;font-weight:900}
.textbook-brand b,.textbook-brand small{display:block}.textbook-brand b{font-size:16px;color:#17344a}.textbook-brand small{font-size:10px;letter-spacing:1.2px;color:#698093;margin-top:3px}
.textbook-actions{display:flex;align-items:center;gap:10px}.textbook-actions>span{font-size:10px;letter-spacing:1px;color:#2c7773;background:#e4f6ef;border-radius:999px;padding:8px 10px;font-weight:800}.textbook-actions button{border:1px solid #d5e0e8;background:#fff;color:#23445a;border-radius:10px;padding:9px 12px;font-size:12px;font-weight:700;cursor:pointer}
.textbook-hero{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(300px,.9fr);gap:clamp(20px,4vw,52px);align-items:center;padding:clamp(24px,4vw,54px);border-radius:26px;background:#122f43;color:#f5fbff;overflow:hidden;position:relative}
.textbook-hero:after{content:"";position:absolute;width:320px;height:320px;border:1px solid #ffffff14;border-radius:50%;right:-110px;top:-130px;pointer-events:none}
.textbook-hero-copy{position:relative;z-index:1}.textbook-eyebrow,.textbook-overline{font-size:11px;font-weight:850;letter-spacing:1.5px;color:#56cdb6}
.textbook-hero h1{font-size:clamp(32px,4vw,54px);line-height:1.04;letter-spacing:-1.5px;color:#fff;margin:17px 0 18px;max-width:720px}
.textbook-hero-copy>p{font-size:17px;line-height:1.8;color:#d5e5ef;max-width:680px}
.textbook-pills{display:flex;flex-wrap:wrap;gap:8px;margin-top:22px}.textbook-pills span{border:1px solid #ffffff30;border-radius:999px;padding:7px 11px;font-size:12px;color:#e7f6f8}
.textbook-hero-footer{display:flex;flex-wrap:wrap;gap:22px;margin-top:30px;padding-top:18px;border-top:1px solid #ffffff25;color:#b5cbd8;font-size:12px}.textbook-hero-footer b{color:#fff;font-size:20px;margin-right:6px}
.textbook-hero-art{min-width:0;display:flex;align-items:center;justify-content:center;min-height:270px;background:#ffffff08;border:1px solid #ffffff14;border-radius:22px;padding:22px}
.lab-visual{width:100%;min-height:220px;display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:15px;position:relative;color:#f3fbff}
.lab-caption{flex-basis:100%;text-align:center;font-size:12px;line-height:1.6;color:#c3d9e5;padding:10px 6px 0}
.lab-orb{width:135px;height:135px;display:flex;flex-direction:column;justify-content:center;align-items:center;border-radius:50%;background:linear-gradient(140deg,#48cbb0,#278a91);font-size:30px;font-weight:900;box-shadow:0 0 0 12px #50cdb015,0 0 40px #45c9ad30}
.lab-orb span{font-size:10px;font-weight:600;text-align:center;margin:6px 8px 0}.lab-link{font-size:11px;color:#a6c6d7}.lab-equation{font-size:26px;font-weight:850;background:#fff;color:#17364a;border-radius:14px;padding:20px}.lab-equation span{color:#168a7e}
.bond-visual .atom{width:78px;height:78px;border-radius:50%;display:flex;flex-direction:column;align-items:center;justify-content:center;background:#65cdb7;color:#12384a;box-shadow:0 0 0 9px #65cdb71a;font-size:20px}.bond-visual .atom span{font-size:10px}.bond-visual .atom-b{background:#a99af6}.bond-line{width:75px;height:5px;background:linear-gradient(90deg,#65cdb7,#a99af6);border-radius:9px}
.particle-box{width:180px;height:155px;border:2px solid #8dc9db;border-radius:14px;position:relative;background:#ffffff08;display:grid;grid-template-columns:repeat(3,1fr);grid-template-rows:repeat(3,1fr);place-items:center;padding:10px}.particle-box i{width:13px;height:13px;border-radius:50%;background:#70dfc1;box-shadow:0 0 12px #70dfc180}.particle-box i:nth-child(2n){background:#b8a8ff}.particle-notes{display:flex;flex-direction:column;gap:5px;font-size:12px}.particle-notes b{color:#fff;margin-top:6px}.particle-notes span{color:#b9d2df}
.ph-visual{display:block;padding:30px 10px}.ph-scale,.ph-labels{display:flex;justify-content:space-between}.ph-scale span,.ph-labels b{font-size:12px}.ph-gradient{height:24px;border-radius:99px;background:linear-gradient(90deg,#e85f6b,#edaa6b,#e9df85,#6fd0b1,#64a9ed,#8b78d9);margin:12px 0}.ph-labels b{color:#d8e9f0}.ph-visual .lab-caption{margin-top:18px}
.equilibrium-visual{gap:10px}.eq-side{display:flex;flex-direction:column;gap:8px;text-align:center;padding:18px 12px;border:1px solid #ffffff30;border-radius:14px;min-width:110px}.eq-side b{font-size:12px}.eq-side span{font-size:10px;color:#b9d2df}.eq-arrows{display:flex;flex-direction:column;color:#67dfc0;font-size:24px}
.redox-electrode{padding:18px 12px;border-radius:12px;background:#dcf7ee;color:#164653;text-align:center;font-weight:900;font-size:13px}.redox-electrode span{display:block;font-weight:600;font-size:11px;margin-top:6px}.redox-electrode.cathode{background:#e7e0ff;color:#463c80}.electron-path{font-size:14px;color:#8be8d4;font-weight:900}
.organic-atom{width:55px;height:55px;display:grid;place-items:center;border-radius:50%;background:#e2f5ed;color:#163f4e;font-size:23px;font-weight:900}.organic-atom.oxygen{background:#ffdcce;color:#843d30}.organic-bond{height:4px;width:32px;background:#a4d8d5;border-radius:5px}
.energy-step{padding:16px 25px;border-radius:12px;font-size:13px;font-weight:900;letter-spacing:.5px}.energy-step.high{background:#f9d9a5;color:#714a12}.energy-step.low{background:#bdeee0;color:#155d55}.energy-down{font-size:12px;color:#c7dce7}
.atom-visual{min-height:230px}.nucleus{z-index:2;width:74px;height:74px;border-radius:50%;background:#f7a46d;display:flex;align-items:center;justify-content:center;gap:5px;box-shadow:0 0 0 10px #f7a46d1e}.nucleus b{background:#fff4e9;color:#6f4933;border-radius:50%;padding:8px;font-size:13px}.orbit{position:absolute;width:220px;height:100px;border:2px solid #83c8d8;border-radius:50%;transform:rotate(-35deg)}.orbit-two{transform:rotate(42deg);width:200px;height:145px;border-color:#a99af6}.orbit i{position:absolute;width:12px;height:12px;border-radius:50%;background:#71e1c4;top:8px;left:42px}
.textbook-section{margin-top:38px}.textbook-section-heading{display:flex;justify-content:space-between;align-items:end;gap:20px;margin-bottom:18px}.textbook-section-heading h2{font-size:clamp(24px,2.5vw,32px);line-height:1.15;letter-spacing:-.6px;color:#19374c;margin:8px 0 0}.textbook-section-heading>p{max-width:400px;font-size:13px;line-height:1.65;color:#688093;margin:0}
.textbook-bigidea{display:flex;gap:15px;align-items:flex-start;padding:22px;border-radius:18px;background:#e4f7f0;border:1px solid #ccebe0}.textbook-star{display:grid;place-items:center;flex:0 0 40px;height:40px;border-radius:12px;background:#c6efdf;color:#126e60;font-size:23px}.textbook-bigidea b{font-size:10px;letter-spacing:1.3px;color:#28776c}.textbook-bigidea p{font-size:15px;line-height:1.8;color:#244d55;margin:7px 0 0}
.textbook-route{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px;margin-top:12px}.textbook-route-item{display:flex;align-items:flex-start;gap:10px;padding:14px;border:1px solid #dce7ed;background:#fff;border-radius:13px;min-width:0}.textbook-route-item>span{flex:0 0 27px;height:27px;display:grid;place-items:center;background:#e8f2fa;color:#2d6583;border-radius:8px;font-size:11px;font-weight:900}.textbook-route-item b{font-size:13px;line-height:1.45;color:#28465b}
.textbook-card-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.textbook-card{min-width:0;background:#fff;border:1px solid #dbe6ed;border-radius:18px;padding:clamp(18px,2vw,26px);box-shadow:0 6px 18px #16384d08}.textbook-card-head{display:flex;align-items:center;justify-content:space-between;gap:10px}.textbook-number{width:36px;height:36px;display:grid;place-items:center;border-radius:11px;background:#15384d;color:#b8f0de;font-size:13px;font-weight:900}.textbook-type{font-size:10px;letter-spacing:1px;color:#287c77;background:#e7f7f2;padding:7px 9px;border-radius:999px;font-weight:850}.textbook-card h3{font-size:21px;line-height:1.25;color:#19384e;margin:16px 0}
.textbook-points{display:grid;gap:9px}.textbook-point{display:grid;grid-template-columns:20px minmax(0,1fr);gap:9px;align-items:start}.textbook-point>span{color:#1b9c8a;font-size:13px;padding-top:3px}.textbook-point p{font-size:14px;line-height:1.75;color:#425d70;margin:0}
.textbook-formula{margin-top:15px;padding:15px;border-radius:12px;background:#eef5ff;border:1px solid #d8e7f8;color:#1a4e70;font-size:16px;line-height:1.7;overflow-wrap:anywhere}
.textbook-takeaway{margin-top:15px;padding:13px 15px;border-radius:12px;background:#fff7e4;border-left:4px solid #e9b85c}.textbook-takeaway b{font-size:10px;letter-spacing:1.1px;color:#926318}.textbook-takeaway p{font-size:13px;line-height:1.65;color:#6c5429;margin:5px 0 0}
.textbook-application-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.textbook-application{position:relative;padding:23px;border-radius:18px;border:1px solid #dce7ed;background:#fff}.textbook-application.example{background:#eef9f5;border-color:#d0eee2}.textbook-application.warning{background:#fff6e8;border-color:#f2e1bd}.application-icon{display:grid;place-items:center;width:38px;height:38px;border-radius:12px;background:#fff;font-size:20px;color:#1b8279;margin-bottom:17px}.textbook-application small{font-size:10px;letter-spacing:1.2px;font-weight:900;color:#57758a}.textbook-application p{font-size:15px;line-height:1.8;color:#28485c;margin:9px 0 0}
.textbook-recall-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.textbook-recall{padding:20px;border:1px solid #dbe6ed;border-radius:17px;background:#fff}.textbook-recall>span{font-size:12px;font-weight:900;color:#168c80}.textbook-recall h3{font-size:17px;line-height:1.45;color:#1d3c51;min-height:50px}.textbook-recall button{border:0;background:#15384d;color:#fff;border-radius:10px;padding:10px 13px;font-size:12px;font-weight:750;cursor:pointer}.textbook-recall-answer{margin-top:13px;padding:12px;border-radius:11px;background:#e8f8f1;color:#23584c;font-size:13px;line-height:1.7}
.textbook-video-section{display:grid;grid-template-columns:minmax(230px,.65fr) minmax(0,1.35fr);gap:24px;align-items:center;margin:38px 0 12px;padding:clamp(20px,3vw,32px);border-radius:22px;background:#112f43;color:#f5fbff}.textbook-video-copy h2{font-size:clamp(23px,2.4vw,31px);line-height:1.2;color:#fff;margin:12px 0}.textbook-video-copy p{font-size:14px;line-height:1.7;color:#c5d9e4}.textbook-video-copy>a{display:inline-block;margin-top:10px;color:#7de3cc;font-size:13px;font-weight:800;text-decoration:none}.textbook-video-frame{aspect-ratio:16/9;min-width:0;border-radius:14px;overflow:hidden;background:#071d2a}.textbook-video-frame iframe{width:100%;height:100%;border:0;display:block}
@media(max-width:850px){.textbook-hero{grid-template-columns:1fr}.textbook-hero-art{min-height:230px}.textbook-route{grid-template-columns:repeat(2,minmax(0,1fr))}.textbook-video-section{grid-template-columns:1fr}.textbook-video-frame{min-height:220px}}
@media(max-width:620px){.textbook-topbar{align-items:flex-start}.textbook-actions{flex-direction:column;align-items:flex-end}.textbook-hero{padding:22px}.textbook-hero h1{font-size:34px}.textbook-card-grid,.textbook-application-grid,.textbook-recall-grid{grid-template-columns:1fr}.textbook-section-heading{display:block}.textbook-section-heading>p{margin-top:9px}.textbook-route{grid-template-columns:1fr 1fr}.textbook-recall h3{min-height:0}.textbook-hero-footer{gap:12px}.textbook-hero-footer b{font-size:17px}}


/* Topic-specific diagrams and chemistry revision tables */
.chem-diagram-wrap{background:linear-gradient(145deg,#f4fafb,#eef4fb);border:1px solid #d6e5ec;border-radius:20px;padding:clamp(18px,3vw,30px);color:#17394d;overflow:hidden}
.chem-diagram-title>span,.chem-table-heading>div>span{font-size:10px;letter-spacing:1.5px;font-weight:900;color:#168b82}
.chem-diagram-title h3,.chem-table-heading h3{font:800 clamp(19px,2.2vw,25px)/1.25 Manrope,sans-serif;letter-spacing:-.5px;color:#17394d;margin:8px 0 22px}
.chem-flow{display:flex;align-items:stretch;justify-content:center;gap:clamp(5px,1.5vw,17px);width:100%}
.chem-node{flex:1;min-width:0;min-height:112px;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:14px 10px;border:1px solid #cbdfe8;border-radius:15px;background:#fff;box-shadow:0 8px 20px #1a4b5c0b}
.chem-node b{font:900 clamp(14px,1.7vw,20px)/1.2 Manrope,sans-serif;color:#1b435a;overflow-wrap:anywhere}
.chem-node span{font-size:12px;line-height:1.55;color:#587184;margin-top:8px;overflow-wrap:anywhere}
.chem-node.teal{background:#e3f8f1;border-color:#a8dfd0}.chem-node.teal b{color:#087c70}
.chem-node.blue{background:#e9f1ff;border-color:#c5d8fa}.chem-node.blue b{color:#315fa5}
.chem-node.gold{background:#fff3dc;border-color:#f0d49c}.chem-node.gold b{color:#8a641b}
.chem-arrow{align-self:center;color:#168e84;font-size:clamp(22px,3vw,34px);font-weight:900;flex:0 0 auto}
.chem-diagram-caption{font-size:13px;line-height:1.7;color:#4e687b;border-top:1px solid #d7e5eb;margin:20px 0 0;padding-top:14px}
.chem-table-wrap{border:1px solid #d7e4eb;border-radius:18px;background:#fff;overflow:hidden;box-shadow:0 8px 24px #16384d08}
.chem-table-heading{display:flex;justify-content:space-between;gap:20px;align-items:end;padding:22px 24px;background:linear-gradient(110deg,#f0faf7,#f3f7ff);border-bottom:1px solid #dce8ee}
.chem-table-heading h3{margin:7px 0 0}.chem-table-heading p{max-width:360px;font-size:12px;line-height:1.6;color:#617b8d;margin:0}
.chem-table-scroll{width:100%;overflow-x:auto}
.chem-reference-table{width:100%;border-collapse:separate;border-spacing:0;font-size:13px;line-height:1.7;color:#415c70}
.chem-reference-table th,.chem-reference-table td{padding:16px 18px;text-align:left;vertical-align:top;border-bottom:1px solid #e6edf1}
.chem-reference-table thead th{background:#15394d;color:#eaf8fc;font-size:10px;letter-spacing:1px;text-transform:uppercase;font-weight:900}
.chem-reference-table thead th:first-child{width:22%}.chem-reference-table thead th:nth-child(2){width:48%}.chem-reference-table thead th:nth-child(3){width:30%}
.chem-reference-table tbody tr:nth-child(even){background:#f7fafc}.chem-reference-table tbody tr:last-child th,.chem-reference-table tbody tr:last-child td{border-bottom:0}
.chem-reference-table tbody th{font-weight:800;color:#1e465d;min-width:170px}
.chem-table-index{display:inline-grid;place-items:center;width:25px;height:25px;margin:0 8px 5px 0;border-radius:7px;background:#e0f5ef;color:#168577;font-size:10px;font-weight:900}
.chem-table-hint{color:#7d93a2;font-style:italic}
@media(max-width:700px){.chem-flow{flex-direction:column;align-items:stretch}.chem-node{min-height:75px}.chem-arrow{transform:rotate(90deg);align-self:center;font-size:25px;line-height:1}.chem-table-heading{display:block}.chem-table-heading p{margin-top:10px}.chem-reference-table{min-width:690px}.chem-reference-table th,.chem-reference-table td{padding:13px}}

/* Compact, readable notes with colourful art and clearly framed tables */
.chem-bullet-notes{margin:0;padding-left:19px;display:grid;gap:7px;color:#38566a;font-size:13px;line-height:1.6}
.chem-bullet-notes li{padding-left:3px}.chem-bullet-notes li::marker{color:#139b8a}
.textbook-card{padding:20px 22px;border:1px solid #cadbe5;border-radius:15px;box-shadow:0 5px 14px #183c5010}
.textbook-card h3{font-size:18px;margin:12px 0;line-height:1.35}.textbook-card-grid{gap:12px}
.textbook-section{margin-top:30px}.textbook-section-heading{margin-bottom:14px}
.chem-table-wrap{border:2px solid #b9ccd9;border-radius:14px;box-shadow:0 8px 22px #173d500b;overflow:hidden}
.chem-table-heading{padding:17px 20px;background:linear-gradient(100deg,#e5f8f1,#e8f0ff);border-bottom:2px solid #b9ccd9}
.chem-reference-table{border-collapse:collapse;font-size:12px;line-height:1.6}.chem-reference-table th,.chem-reference-table td{padding:12px 14px;border:1px solid #cfdae2}
.chem-reference-table thead th{background:#173d52;color:#fff;border-color:#436579}.chem-reference-table tbody th{background:#edf6fa;min-width:155px}
.chem-reference-table tbody tr:nth-child(even) td{background:#f4fafc}.chem-reference-table tbody tr:hover td{background:#e9f8f2}
.chem-art{height:145px;max-width:440px;width:100%;margin:0 auto 14px;position:relative;overflow:hidden;border-radius:24px;background:linear-gradient(135deg,#d6fff0,#d8e8ff 50%,#fff0c9)}
.chem-art:before{content:"";position:absolute;inset:15%;border-radius:50%;background:radial-gradient(circle,#ffffffdd,transparent 70%)}
.chem-art i{position:absolute;width:58px;height:58px;border-radius:50%;box-shadow:inset -8px -9px 14px #164c5b33,0 8px 20px #164c5b20}
.chem-art i:nth-child(1){left:18%;top:35%;background:linear-gradient(135deg,#4f9dff,#7458e8)}
.chem-art i:nth-child(2){left:44%;top:18%;background:linear-gradient(135deg,#38dfb1,#0a9c91)}
.chem-art i:nth-child(3){left:69%;top:47%;background:linear-gradient(135deg,#ffd16b,#ff8e6e)}
.chem-art b{position:absolute;color:#176f9b;font-size:30px;filter:drop-shadow(0 3px 0 #fff)}
.chem-art b:nth-of-type(1){left:32%;top:20%;transform:rotate(-20deg)}.chem-art b:nth-of-type(2){left:56%;top:48%;transform:rotate(25deg)}
@media(max-width:700px){.chem-art{height:125px}.chem-art i{width:45px;height:45px}.chem-reference-table{min-width:650px}.chem-reference-table th,.chem-reference-table td{padding:10px}.textbook-card{padding:17px}}

/* Individual topic illustrations embedded in every note */
.topic-illustration{display:block;width:100%;height:auto;min-height:220px;max-height:360px;object-fit:contain;border-radius:22px;background:#0b1728;border:1px solid #263b56;box-shadow:0 18px 44px #02081266}
.textbook-hero-art{display:flex;flex-direction:column;gap:14px;min-width:0}
@media(max-width:760px){.topic-illustration{min-height:170px;max-height:250px}.textbook-hero-art{margin-top:16px}}

/* Visual Lab — topic-linked study gallery */
.textbook-visual-gallery{padding-top:8px}
.chem-visual-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:22px}
.chem-visual-card{min-width:0;overflow:hidden;border:1px solid var(--line);border-radius:20px;background:linear-gradient(155deg,#12263a,#0b1727);padding:18px;box-shadow:0 12px 28px #02081222}
.chem-visual-main{background:linear-gradient(155deg,#132e40,#0b1727)}
.chem-visual-label{display:inline-flex;align-items:center;gap:7px;color:var(--teal);font-size:10px;font-weight:800;letter-spacing:.13em}
.chem-visual-art{height:210px;display:flex;align-items:center;justify-content:center;margin:12px 0 16px;border:1px solid #ffffff12;border-radius:14px;background:radial-gradient(ellipse at 50% 45%,#183b50 0%,#0a1727 75%);overflow:hidden}
.chem-visual-art>svg{width:100%;height:100%;max-height:210px}
.chem-visual-card h3{font-size:17px;line-height:1.3;margin:8px 0;color:var(--text)}
.chem-visual-card p{font-size:12px;color:var(--muted);line-height:1.65;margin:0}
.chem-visual-scheme{padding:8px}
.chem-visual-scheme svg{max-width:100%}
.chem-visual-reference{height:210px;display:flex;flex-direction:column;justify-content:center;padding:12px;gap:10px}
.visual-reference-row{display:grid;grid-template-columns:78px minmax(0,1fr);gap:9px;padding:10px;border:1px solid #2b4259;border-radius:10px;background:#0d1c2d}
.visual-reference-row b{font-size:9px;letter-spacing:.08em;color:var(--amber);align-self:start}
.visual-reference-row span{font-size:11px;line-height:1.5;color:var(--text)}
@media(max-width:900px){.chem-visual-grid{grid-template-columns:1fr 1fr}.chem-visual-main{grid-column:1/-1}}
@media(max-width:560px){.chem-visual-grid{grid-template-columns:1fr}.chem-visual-main{grid-column:auto}.chem-visual-art{height:190px}}
@media print{.chem-visual-grid{grid-template-columns:repeat(3,1fr)}.chem-visual-card{break-inside:avoid;background:#fff;color:#172435;border-color:#bbb}.chem-visual-card p,.visual-reference-row span{color:#34495e}}

/* GchemIB redesign pass: editorial chemistry field guide */
:root{--bg:#f4f7f6;--panel:#ffffff;--panel2:#edf4f1;--line:#dce7e2;--text:#172c2b;--muted:#617875;--teal:#087f73;--blue:#3f6fbb;--purple:#7457a6;--amber:#a96b0b;--radius:18px;--shadow:0 12px 34px rgba(21,54,48,.08)}
html{background:var(--bg)}body{background:var(--bg);color:var(--text);font-family:"DM Sans",sans-serif}.app-shell{background:var(--bg)}.sidebar{background:#102d2a;color:#f0fbf7;border-right:0}.sidebar .brand-copy small,.sidebar .nav-copy small,.sidebar .sidebar-topline,.sidebar .nav-group-label,.sidebar .sidebar-course-chip small,.sidebar .sidebar-foot{color:#a6c5bb}.sidebar .nav-link{color:#dcece6;border-color:transparent}.sidebar .nav-link:hover,.sidebar .nav-link.active{background:#1d4540;border-color:#2e5a52}.sidebar .nav-link.active .nav-active-arrow{color:#70e0c5}.sidebar .sidebar-course-chip,.sidebar .sidebar-journey-card{background:#173a35;border-color:#2a5149}.sidebar .brand-mark{color:#70e0c5}.main-area{background:var(--bg)}.topbar{background:rgba(244,247,246,.92);border-color:var(--line);backdrop-filter:blur(18px)}.breadcrumbs,.breadcrumbs strong{color:var(--text)}.global-search{background:#fff;border-color:var(--line);box-shadow:0 3px 10px #183b3010}.global-search input{color:var(--text)}.content-wrap{max-width:1440px}.hero{border:1px solid #d8e8e1;background:linear-gradient(125deg,#e4f4ed 0%,#f7fbf8 52%,#e7effb 100%);border-radius:28px;box-shadow:var(--shadow);overflow:hidden}.hero h1{color:#153b35;letter-spacing:-.055em}.hero h1 span{color:#087f73}.hero p{color:#52706a}.hero-visual{background:radial-gradient(ellipse at 50% 45%,#d2eee5 0%,#e9f4f0 55%,#e4edf9 100%);border-radius:24px}.floating-chip{background:#fff;color:#254740;border:1px solid #d9e8e2;box-shadow:0 8px 24px #143b2e14}.section-heading h2,.textbook-section-heading h2{letter-spacing:-.035em;color:var(--text)}.feature-card,.stat-card,.panel,.tool-card,.topic-card{background:#fff;border:1px solid var(--line);box-shadow:0 8px 24px #183b3008;border-radius:18px}.feature-card:hover,.topic-button:hover{border-color:#85bdb0;box-shadow:0 12px 30px #183b3012;transform:translateY(-2px)}button,.btn{transition:background .18s,border-color .18s,box-shadow .18s,transform .18s}.btn-primary{background:#087f73;color:#fff;box-shadow:0 8px 20px #087f7325}.btn-primary:hover{background:#06685f}.btn-ghost{background:#fff;border-color:#cdded7;color:#24534b}.page{animation:page-in .28s ease both}@keyframes page-in{from{opacity:0;transform:translateY(5px)}to{opacity:1;transform:translateY(0)}}
/* Reading layout */
#note-reader{max-width:1200px;margin-inline:auto}.textbook-topbar{background:#fff;border:1px solid var(--line);border-radius:15px;padding:14px 18px;margin-bottom:18px}.textbook-brand-mark{background:#dff4eb;color:#087f73;border-radius:10px}.textbook-brand b{color:#173b35}.textbook-brand small{color:#728a82}.textbook-actions button{background:#f2f8f5;color:#28594f;border:1px solid #dce9e3;border-radius:10px;padding:8px 12px}.textbook-hero{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(260px,.85fr);gap:26px;align-items:center;padding:clamp(24px,4vw,48px);background:linear-gradient(125deg,#123c36,#17584d 70%,#1b6559);border-radius:26px;color:#f2fff9;overflow:hidden;position:relative;box-shadow:0 18px 42px #103d3324}.textbook-hero:after{content:"";position:absolute;width:320px;height:320px;border:1px solid #ffffff1c;border-radius:50%;right:10%;top:-45%;box-shadow:0 0 0 35px #ffffff08,0 0 0 70px #ffffff06;pointer-events:none}.textbook-hero-copy,.textbook-hero-art{position:relative;z-index:1}.textbook-hero h1{font-size:clamp(30px,4vw,52px);line-height:1.04;letter-spacing:-.055em;max-width:720px;color:#fff}.textbook-hero p{max-width:680px;color:#c8e4db;font-size:15px;line-height:1.8}.textbook-eyebrow,.textbook-overline{color:#78e0c6;letter-spacing:.15em;font-size:10px;font-weight:800}.textbook-hero-footer{display:flex;flex-wrap:wrap;gap:10px;margin-top:25px}.textbook-hero-footer span{border:1px solid #ffffff24;background:#ffffff0b;border-radius:11px;padding:9px 12px;color:#d5eee5;font-size:11px}.textbook-hero-footer b{color:#fff}.topic-illustration{width:100%;height:auto;max-height:310px;filter:drop-shadow(0 15px 22px #001c1633)}.textbook-section{margin:28px 0;padding:clamp(18px,2.5vw,28px);background:#fff;border:1px solid var(--line);border-radius:22px;box-shadow:0 8px 26px #183b3007}.textbook-section-heading{display:flex;align-items:end;justify-content:space-between;gap:18px;margin-bottom:20px}.textbook-section-heading h2{font-size:clamp(21px,2.4vw,29px);margin:5px 0 0}.textbook-section-heading p{color:var(--muted);font-size:12px;max-width:360px}.textbook-route{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}.textbook-route-item{display:flex;align-items:center;gap:10px;padding:14px;background:#f4f8f6;border:1px solid #e0ebe5;border-radius:13px;font-size:12px}.textbook-route-item>span{display:grid;place-items:center;flex:0 0 30px;height:30px;border-radius:9px;background:#dff3eb;color:#087f73;font-size:10px;font-weight:800}.textbook-card-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:13px}.textbook-card{padding:20px;border:1px solid #e0e9e5;border-radius:16px;background:linear-gradient(145deg,#fff,#f8fbf9)}.textbook-card-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:12px}.textbook-number{display:grid;place-items:center;width:32px;height:32px;border-radius:10px;background:#e0f4ec;color:#087f73;font-weight:800}.textbook-type{font-size:9px;font-weight:800;letter-spacing:.12em;color:#68827a}.textbook-card h3{font-size:17px;color:#173b35;letter-spacing:-.02em}.chem-bullet-notes{padding-left:18px;color:#506a63;line-height:1.8}.chem-bullet-notes li{padding-left:3px;margin:6px 0}.textbook-card li::marker{color:#0d9a82}.textbook-table,.textbook-section table{width:100%;border-collapse:separate;border-spacing:0;overflow:hidden;border:1px solid #dce8e2;border-radius:13px}.textbook-table th,.textbook-section table th{background:#e8f4ef;color:#214b42;text-align:left;font-size:11px}.textbook-table td,.textbook-table th,.textbook-section table td,.textbook-section table th{padding:12px 14px;border-right:1px solid #dce8e2;border-bottom:1px solid #dce8e2;vertical-align:top}.textbook-table tr:last-child td,.textbook-section table tr:last-child td{border-bottom:0}.textbook-table td,.textbook-section table td{color:#4f6962;font-size:12px}.textbook-application-grid,.textbook-recall-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.textbook-application{border-radius:16px;padding:20px;border:1px solid #dce8e2;background:#f6faf8}.textbook-application.warning{background:#fff8e9;border-color:#f0dfb9}.textbook-application small{font-weight:800;letter-spacing:.12em;color:#087f73}.textbook-application.warning small{color:#a96b0b}.textbook-recall{border:1px solid #dce8e2;background:#f8fbf9;border-radius:15px;padding:18px}.textbook-recall>span{color:#087f73;font-weight:800;font-size:11px}.textbook-recall h3{font-size:15px}.textbook-recall button{background:#e2f4ed;color:#17675a;border:1px solid #cbe8dc;border-radius:9px;padding:8px 11px}.textbook-recall-answer{margin-top:12px;padding:12px;background:#fff;border-radius:10px;color:#4b655d;font-size:12px;line-height:1.7}.textbook-video-section{display:grid;grid-template-columns:.75fr 1.25fr;gap:22px;align-items:center;background:#122f2b;color:#f2fff9;border-radius:22px;padding:22px}.textbook-video-copy h2{color:#fff}.textbook-video-copy p{color:#c1ddd4}.textbook-video-copy a{display:inline-block;margin-top:8px;color:#7ce2c8}.textbook-video-frame{aspect-ratio:16/9;overflow:hidden;border-radius:14px;background:#071b18}.textbook-video-frame iframe{width:100%;height:100%;border:0}
/* Visual lab should be a real part of the reading flow, not a second hero */
.textbook-visual-gallery{background:transparent;border:0;box-shadow:none;padding:0;margin:24px 0}.chem-visual-grid{display:grid;grid-template-columns:1.2fr 1fr 1fr;gap:14px}.chem-visual-card{background:#fff;border:1px solid var(--line);border-radius:18px;padding:16px;box-shadow:0 7px 22px #183b3007;min-width:0}.chem-visual-card h3{font-size:16px;color:#173b35}.chem-visual-card p{color:#617875;line-height:1.7;font-size:12px}.chem-visual-label{font-size:9px;font-weight:800;letter-spacing:.12em;color:#087f73}.chem-visual-art{height:190px;margin:12px 0;display:flex;align-items:center;justify-content:center;border-radius:13px;background:radial-gradient(circle at 50% 40%,#e0f4eb,#f2f7f5 70%);border:1px solid #e0ebe5;overflow:hidden}.chem-visual-art>svg{width:100%;height:100%;max-height:190px}.chem-visual-reference{padding:12px;gap:8px}.visual-reference-row{display:grid;grid-template-columns:68px minmax(0,1fr);gap:8px;background:#f6faf8;border:1px solid #e0ebe5;border-radius:9px;padding:9px}.visual-reference-row b{font-size:8px;color:#087f73}.visual-reference-row span{font-size:10px;color:#405d55;line-height:1.45}
@media(max-width:1000px){.textbook-hero{grid-template-columns:1fr}.textbook-hero-art{max-width:420px;margin:auto}.chem-visual-grid{grid-template-columns:1fr 1fr}.chem-visual-main{grid-column:1/-1}.textbook-route{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:650px){.chem-visual-grid,.textbook-card-grid,.textbook-application-grid,.textbook-recall-grid,.textbook-video-section{grid-template-columns:1fr}.chem-visual-main{grid-column:auto}.textbook-section-heading{display:block}.textbook-route{grid-template-columns:1fr}.textbook-hero{padding:23px}.textbook-hero h1{font-size:32px}.textbook-actions{gap:6px}.textbook-table td,.textbook-table th,.textbook-section table td,.textbook-section table th{padding:9px;font-size:11px}}
@media print{body,.main-area{background:#fff}.sidebar,.topbar,.textbook-actions,.textbook-video-section{display:none!important}.textbook-hero{background:#fff;color:#173b35;border:1px solid #bbb;box-shadow:none}.textbook-hero h1,.textbook-hero p{color:#173b35}.textbook-section,.textbook-card,.chem-visual-card{box-shadow:none;break-inside:avoid}}


/* Readable visual labels: keep all chemistry text horizontal */
.topic-visual-board,.topic-visual-card,.topic-visual-card figcaption,
.chem-visual-card,.chem-visual-card h3,.chem-visual-card p,
.chem-visual-label,.visual-reference-row,.visual-reference-row b,
.visual-reference-row span,.chem-diagram-wrap,.chem-diagram-title,
.chem-node,.chem-node b,.chem-node span,.chem-diagram-caption {
  writing-mode: horizontal-tb !important;
  text-orientation: mixed !important;
  word-break: normal;
  overflow-wrap: break-word;
  hyphens: auto;
}
.chem-visual-grid {
  grid-template-columns: repeat(3, minmax(250px, 1fr));
  align-items: stretch;
}
.chem-visual-card,.chem-visual-art { min-width: 0; }
.visual-reference-row {
  grid-template-columns: minmax(74px, 0.36fr) minmax(0, 1fr);
  align-items: start;
}
.visual-reference-row b,.visual-reference-row span {
  display: block;
  white-space: normal;
  line-height: 1.5;
}
.chem-flow {
  display: flex;
  flex-direction: row;
  align-items: stretch;
  gap: clamp(6px, 1vw, 14px);
  overflow-x: auto;
  padding: 4px 2px 10px;
}
.chem-node {
  flex: 1 0 120px;
  min-width: 120px;
  white-space: normal;
}
.chem-node b,.chem-node span { max-width: 100%; }
.chem-arrow { writing-mode: horizontal-tb !important; transform: none !important; }
@media(max-width:900px) {
  .chem-visual-grid { grid-template-columns: repeat(2, minmax(220px, 1fr)); }
  .chem-visual-main { grid-column: 1 / -1; }
}
@media(max-width:620px) {
  .chem-visual-grid { grid-template-columns: minmax(0, 1fr); }
  .chem-visual-main { grid-column: auto; }
  .chem-flow { flex-direction: row; }
  .chem-node { flex-basis: 105px; min-width: 105px; }
  .visual-reference-row { grid-template-columns: 82px minmax(0, 1fr); }
}


/* GchemIB final visual direction: clean editorial study site, no pictures */
:root {
  --bg:#f5f7f6;
  --panel:#ffffff;
  --panel2:#edf3f0;
  --line:#dce5e0;
  --text:#20332e;
  --muted:#687a73;
  --teal:#187b68;
  --blue:#4b6fa9;
  --purple:#7664a1;
  --amber:#a87325;
  --radius:16px;
  --shadow:0 8px 26px rgba(28,55,44,.06);
}
body,.app-shell,.main-area { background:#f5f7f6!important; color:#20332e; }
.sidebar { background:#173b32!important; color:#f4faf6; box-shadow:3px 0 18px #173b3210; }
.sidebar .nav-link { color:#d7e6de; }
.sidebar .nav-link:hover,.sidebar .nav-link.active { background:#285548!important;border-color:#3b6d5a!important; }
.sidebar .brand-mark { background:#d9eee2!important;color:#1b5a49!important;box-shadow:none; }
.topbar { background:rgba(249,251,249,.96)!important;border-color:#dce5e0!important; }
.content-wrap { max-width:1380px; }
.hero {
  display:block!important;min-height:0!important;
  background:linear-gradient(120deg,#e4f1e9 0%,#f8faf8 75%)!important;
  border:1px solid #d8e6dc!important;border-radius:24px!important;
  box-shadow:0 10px 28px #1c49300a!important;
}
.hero-copy { padding:clamp(26px,4vw,48px)!important;max-width:800px; }
.hero h1 { color:#1c4639!important; }
.hero h1 span { color:#187b68!important; }
.hero-copy>p { color:#5b7067!important; }
.hero-visual,.molecule,.orb,.visual-caption,.floating-chip,
.topic-visual-board,.textbook-visual-gallery,.chem-visual-grid,
.chem-art,.topic-illustration,.textbook-hero-art,
img.topic-visual-image,.topic-visual-card img {
  display:none!important;
}
.textbook-hero {
  display:block!important;
  background:linear-gradient(120deg,#17483c,#206451)!important;
  border:0!important;border-radius:22px!important;
  box-shadow:0 12px 28px #17483c18!important;
  padding:clamp(24px,4vw,42px)!important;
}
.textbook-hero:after { display:none!important; }
.textbook-hero-copy { max-width:900px; }
.textbook-hero h1 { max-width:850px;color:#fff!important; }
.textbook-hero p { color:#d8e9e0!important; }
.textbook-hero-footer span { background:#ffffff0d!important;border-color:#ffffff2a!important; }
.textbook-section {
  background:#fff!important;border:1px solid #dce5e0!important;
  border-radius:18px!important;box-shadow:0 5px 18px #1b3c2d08!important;
}
.textbook-section-heading h2,.section-heading h2 { color:#203d32!important; }
.textbook-card {
  background:#fff!important;border:1px solid #dfe8e2!important;
  border-radius:15px!important;box-shadow:none!important;
}
.textbook-card h3 { color:#244c3e!important; }
.textbook-number { background:#e5f2e9!important;color:#187b68!important; }
.textbook-type { color:#74867d!important; }
.chem-bullet-notes,.note-reader p,.note-reader li { color:#4f665c!important; }
.note-callout { background:#edf7f0!important;border-left-color:#23866c!important;color:#315b4b!important; }
.example-box { background:#f7faf8!important;border-color:#dce8e0!important; }
.example-box strong { color:#187b68!important; }
.chem-diagram-wrap {
  background:#fff!important;border:1px solid #dce5e0!important;
  border-radius:16px!important;box-shadow:none!important;
}
.chem-diagram-title h3 { color:#234b3e!important; }
.chem-node { box-shadow:none!important;border-radius:12px!important; }
.chem-diagram-caption { color:#5e736a!important; }
.chem-table-wrap { border-color:#d5e1d9!important;box-shadow:none!important; }
.chem-table-heading { background:#edf5ef!important; }
.chem-reference-table thead th { background:#214e40!important; }
.chem-reference-table tbody th { background:#f0f6f2!important;color:#2d5042!important; }
.chem-reference-table tbody tr:nth-child(even) td { background:#f8faf8!important; }
.feature-card,.panel,.formula-card,.calculator-card,.practice-main,.practice-side,
.tutor-chat,.tool-card,.topic-button,.textbook-topbar {
  box-shadow:none!important;
}
.feature-card,.panel,.formula-card,.calculator-card,.practice-main,.practice-side,
.tutor-chat,.tool-card { background:#fff!important;border-color:#dce5e0!important; }
.feature-card:hover,.topic-button:hover { border-color:#9bbfac!important;box-shadow:0 8px 18px #173b320a!important; }
.btn-primary { background:#187b68!important;color:#fff!important;box-shadow:none!important; }
.btn-primary:hover { background:#126653!important; }
.btn-ghost,.btn-secondary { background:#fff!important;color:#315c4b!important;border-color:#d2dfd7!important; }
.feature-icon.teal { background:#e0f1e7!important;color:#187b68!important; }
.feature-icon.blue { background:#e8eef9!important;color:#4b6fa9!important; }
.feature-icon.purple { background:#eee9f7!important;color:#7664a1!important; }
.feature-icon.amber { background:#f8efdd!important;color:#a87325!important; }
.textbook-video-section { background:#173f35!important; }
@media(max-width:760px) {
  .hero-copy { padding:25px!important; }
  .textbook-hero { padding:24px!important; }
  .textbook-hero h1 { font-size:clamp(28px,8vw,38px)!important; }
}


/* GchemIB palette refresh — midnight navy, electric cyan, violet */
:root{
 --bg:#0b1020;--panel:#121a2e;--panel2:#18223a;--line:#2a3654;
 --text:#f2f5ff;--muted:#a1acc8;--teal:#55e6d0;--blue:#83a7ff;
 --purple:#c3a0ff;--amber:#ffc66d;--radius:18px;
 --shadow:0 14px 38px rgba(0,0,0,.22);
}
body,.app-shell,.main-area{background:#0b1020!important;color:#f2f5ff!important}
.sidebar{background:#080d1b!important;color:#f2f5ff!important;border-right:1px solid #26314c!important}
.sidebar .brand-copy small,.sidebar .sidebar-foot,.sidebar .sidebar-label{color:#8f9bb9!important}
.sidebar .nav-link{color:#b6c1dc!important}
.sidebar .nav-link:hover,.sidebar .nav-link.active{background:#182642!important;border-color:#344b75!important;color:#fff!important}
.sidebar .brand-mark{background:linear-gradient(135deg,#55e6d0,#83a7ff)!important;color:#0b1020!important}
.topbar{background:rgba(11,16,32,.94)!important;border-color:#27324d!important}
.breadcrumbs,.breadcrumbs strong{color:#d9e2fb!important}
.global-search,.search-field,.toolbar select,.icon-button{background:#121a2e!important;border-color:#2a3654!important;color:#dfe7ff!important}
.global-search input,.search-field input{color:#f2f5ff!important}
.hero{background:linear-gradient(125deg,#17294a 0%,#151d37 58%,#211b43 100%)!important;border-color:#34456d!important;box-shadow:0 14px 36px #03061155!important}
.hero h1,.hero h1 span{color:#f2f5ff!important}
.hero h1 span{color:#55e6d0!important}
.hero-copy>p{color:#bdc9e6!important}
.section-heading h2,.textbook-section-heading h2,.page-intro h1{color:#f2f5ff!important}
.feature-card,.panel,.formula-card,.calculator-card,.practice-main,.practice-side,.tutor-chat,.tool-card,.topic-button,.textbook-topbar,.textbook-section,.textbook-card{
 background:#121a2e!important;border-color:#2a3654!important;color:#f2f5ff!important
}
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.textbook-recall button{background:#183b43!important;color:#70edda!important;border-color:#2a6669!important}
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.quiz-option.correct{background:#143c38!important;border-color:#37bda8!important}
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.formula-tag,.tiny-pill{background:#173b43!important;color:#70edda!important;border-color:#2a6669!important}
.element-cell{background:#1a2b49!important;border-color:#354b72!important;color:#f2f5ff!important}
.element-cell.cat-nonmetal{background:#143c3a!important;border-color:#287a70!important}
.element-cell.cat-metalloid{background:#302448!important;border-color:#72569b!important}
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.detail-symbol,.ai-avatar{background:#173b43!important;color:#55e6d0!important}
@media(max-width:760px){.topbar{background:rgba(11,16,32,.97)!important}}


/* GchemIB — clean editorial palette: warm paper, graphite, cobalt and coral */
:root{
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}
html,body,.app-shell,.main-area{background:#f5f4f0!important;color:#222a32!important}
.sidebar{background:#202a35!important;color:#f8f7f3!important;border-right:0!important}
.sidebar .brand-copy small,.sidebar .sidebar-foot,.sidebar .sidebar-label{color:#b8c0c7!important}
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.global-search input,.search-field input{color:#222a32!important}
.hero{background:#fff!important;border:1px solid #e2e1dc!important;box-shadow:0 8px 26px rgba(30,38,46,.045)!important}
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@media(max-width:760px){.topbar{background:#f5f4f0!important}}

/* --- bespoke chemistry schemes + exam cells --- */
.scheme-fig{width:100%}
.scheme-fig svg{width:100%;height:auto;display:block}
.scheme-fig svg text{font-family:'Manrope',sans-serif}
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.chem-exam-cell{color:#9fe8dd}
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@media print{.chem-visual-card{break-inside:avoid}.chem-visual-card::before{display:none}}

/* hover polish for visual cards */
.chem-visual-card{transition:transform .25s ease,box-shadow .25s ease}
.chem-visual-card:hover{transform:translateY(-3px);box-shadow:0 12px 32px rgba(0,0,0,.35)}
.scheme-fig svg{filter:drop-shadow(0 4px 14px rgba(66,228,210,.12))}