:root{--paper:#f7f5ef;--sheet:#fffefa;--ink:#253a32;--green:#234d41;--sage:#e7ecdf;--muted:#6c776c;--line:#dcded1;--red:#a75645;--gold:#a57a35;--serif:'Songti SC','STSong','Noto Serif CJK SC',serif;--sans:'PingFang SC','Hiragino Sans GB','Microsoft YaHei',sans-serif}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:150px}body{margin:0;color:var(--ink);background:var(--paper);font:15px/1.8 var(--sans)}a{color:var(--green);text-underline-offset:4px}a,button,input,select,textarea{-webkit-tap-highlight-color:transparent}a:hover{color:#a05f42}button,input,textarea,select{font:inherit;color:inherit}button{cursor:pointer}button,a,input,select,textarea,summary{touch-action:manipulation}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible,summary:focus-visible{outline:3px solid var(--gold);outline-offset:4px}h1,h2,h3,p{margin-top:0}h1,h2{font-family:var(--serif);font-weight:600}h1{font-size:38px;line-height:1.5;letter-spacing:-.8px}h2{font-size:26px;line-height:1.5}h3{font-size:17px;line-height:1.7}button{border:0}small,.small{font-size:12px}.muted{color:var(--muted)}.eyebrow{font:10px/1.6 var(--sans);letter-spacing:1.6px;color:var(--muted);display:block}.row{display:flex;align-items:center;gap:14px;flex-wrap:wrap}.spread{justify-content:space-between}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap}.skip{position:fixed;z-index:50;left:15px;top:-100px;background:var(--green);color:white;padding:10px}.skip:focus{top:10px}.site-header{background:rgba(247,245,239,.98);position:sticky;top:0;z-index:20;border-bottom:1px solid var(--line)}.header-top,.header-bottom{max-width:1500px;margin:auto;padding:0 42px;display:flex;align-items:center;justify-content:space-between;gap:30px}.header-top{height:86px}.brand{display:flex;gap:11px;align-items:center;text-decoration:none;font-size:18px;font-family:var(--serif);font-weight:700;letter-spacing:1px;white-space:nowrap}.brand small{display:block;font:8px/1.8 Georgia,serif;letter-spacing:2px;color:var(--muted)}.brand-mark{display:grid;place-items:center;border:1px solid #9da991;border-radius:50%;width:37px;height:37px;font:30px/1 Georgia,serif}.search-wrap{position:relative;max-width:410px;flex:1;display:flex;align-items:center;border-bottom:1px solid #c1c8b9;gap:10px}.search-wrap>span{font-size:25px;line-height:1}.search-wrap input{border:0;background:none;width:100%;font-size:12px;padding:9px 0;min-width:0;outline-offset:1px}.mode-switch{background:#e9eadf;padding:4px;display:flex;border-radius:5px;gap:2px;flex-shrink:0}.mode-switch button{font-size:11px;background:none;padding:7px 11px;border-radius:3px;color:#6f786b;white-space:nowrap}.mode-switch button[aria-pressed=true]{color:#fff;background:var(--green);box-shadow:0 2px 5px #152b1d14}.header-bottom{height:49px;border-top:1px solid #e7e7dc}.header-bottom nav{display:flex;gap:32px;height:100%;align-items:stretch}.header-bottom nav a{display:flex;align-items:center;font-size:13px;text-decoration:none;color:var(--muted);position:relative}.header-bottom nav a[aria-current=page]{color:var(--green);font-weight:600}.header-bottom nav a[aria-current=page]:after{content:'';position:absolute;height:3px;bottom:-1px;left:0;right:0;background:var(--green)}.edition{font-size:10px;color:var(--muted)}#main{min-height:65vh;max-width:1440px;margin:auto;padding:0 42px 60px;outline:none}.primary,.secondary,.text-link,.circle-link{display:inline-flex;align-items:center;justify-content:center;gap:8px;text-decoration:none;font-size:12px;line-height:1.6}.primary{background:var(--green);color:#fff;border:1px solid var(--green);padding:11px 20px;border-radius:4px}.primary:hover{background:#326453;color:white}.secondary{background:transparent;border:1px solid #cbd1c2;padding:10px 16px;border-radius:4px}.secondary:hover{background:#eaeddf;color:var(--green)}.text-link{font-size:12px;border-bottom:1px solid #b4bdac;padding:4px 0}.text-button{background:none;color:var(--green);padding:3px 0;font-size:12px;text-align:left}.circle-link{border:1px solid #b7c2ae;width:42px;height:42px;border-radius:50%;font-size:22px;flex-shrink:0}.home-hero{display:grid;grid-template-columns:1.1fr .9fr;gap:36px;min-height:478px;border-bottom:1px solid var(--line);position:relative}.hero-copy{padding:52px 0 36px}.hero-copy h1{font:50px/1.5 var(--serif);letter-spacing:-1px;margin:18px 0 18px}.hero-copy p{font-size:13px;color:var(--muted);line-height:1.95}.hero-actions{margin-top:28px}.hero-meta{display:flex;gap:30px;margin-top:35px;color:#687b67;font:24px/1 Georgia,serif}.hero-meta>span{display:flex;align-items:center;gap:9px}.hero-meta small{font:10px/1.5 var(--sans);color:var(--muted)}.hero-anatomy{background:radial-gradient(ellipse at 55% 52%,#e9ece0 0,#eeeee450,transparent 70%);position:relative;display:flex;align-items:center;justify-content:center;padding:34px 20px 66px;overflow:hidden}.hero-anatomy:after{content:'';position:absolute;left:18%;right:13%;top:18%;bottom:18%;border:1px solid #bcc6b63b;border-radius:50%;pointer-events:none}.hero-anatomy img{height:330px;width:100%;object-fit:contain;filter:saturate(.68);transform:rotate(-8deg)}.specimen-label{position:absolute;left:18px;top:33px;color:#7a8875;font:9px Georgia,serif;letter-spacing:2px}.anatomy-caption{position:absolute;bottom:30px;left:30px;right:20px;display:flex;justify-content:space-between;gap:10px;font-size:10px;color:var(--muted)}.anatomy-caption a{white-space:nowrap}.dashboard-strip{display:grid;grid-template-columns:1.3fr 48px 1fr 1.25fr;gap:25px;align-items:center;border-bottom:1px solid var(--line);padding:24px 0;margin-bottom:42px}.dashboard-strip h3{margin:5px 0;font-size:14px}.dashboard-strip h3 small{font-size:11px;font-weight:400}.dashboard-strip p,.dashboard-strip a:not(.circle-link){font-size:11px;color:var(--muted);margin:0}.section-heading{display:flex;align-items:end;justify-content:space-between;gap:18px;margin:0 0 24px}.section-heading h2{margin:7px 0 0;font-size:28px}.section-heading>a{font-size:12px;white-space:nowrap}.topic-grid{display:grid;grid-template-columns:repeat(3,1fr);border-top:1px solid var(--line);border-left:1px solid var(--line)}.topic-card{display:flex;gap:18px;padding:25px 23px 24px;border-right:1px solid var(--line);border-bottom:1px solid var(--line);text-decoration:none;transition:background .2s;min-height:180px}.topic-card:hover{background:#ebeedf}.topic-index{font:27px/1 Georgia,serif;color:#a3b09a;margin-top:4px}.topic-card h3{font:22px/1.5 var(--serif);margin:8px 0}.topic-card h3 span{float:right;color:#8a9e83;font:18px Georgia,serif;margin:5px 0 0 20px}.topic-card p{font-size:12px;color:var(--muted);margin:0 0 14px;line-height:1.8}.topic-card small{font-size:10px;color:#809078}.study-method{background:#e9ede0;padding:28px 32px;margin-top:35px;border-radius:4px}.study-method h2{font-size:26px;margin:10px 0 25px}.three-col{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}.three-col p{font-size:12px;color:#64765f;margin:0}.three-col b{display:block;color:var(--green);margin-bottom:9px}.site-footer{border-top:1px solid var(--line);max-width:1356px;margin:0 auto;padding:24px 0 30px;display:flex;align-items:center;gap:28px;font-size:10px;color:var(--muted);flex-wrap:wrap}.site-footer span:last-child{margin-left:auto}.page-head{display:flex;justify-content:space-between;align-items:end;padding:40px 0 28px;gap:20px}.page-head h1{margin:10px 0;font-size:36px}.page-head p{font-size:13px;color:var(--muted);margin-bottom:0}.chapter-number{font:76px/1 Georgia,serif;color:#d2d9c7}.filterbar{display:flex;align-items:center;flex-wrap:wrap;gap:16px;background:#eeeee5;border:1px solid var(--line);padding:14px 20px;border-radius:5px;margin-bottom:30px}.filterbar label{font-size:11px;display:flex;align-items:center;gap:8px}.filterbar small{margin-left:auto;font-size:10px;color:var(--muted)}select{background:var(--sheet);border:1px solid #cdd2c4;border-radius:3px;font-size:12px;padding:7px 25px 7px 9px;max-width:100%}.filter-toggle{font-size:11px;border:1px solid #cdd2c4;background:none;padding:8px 12px;border-radius:3px}.filter-toggle[aria-pressed=true]{background:#234d41;color:white;border-color:#234d41}.topic-section{margin:35px 0 46px}.topic-section .section-heading h2{font-size:26px}.topic-section .section-heading .muted{font-size:11px}.lesson-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px}.lesson-card{border:1px solid var(--line);border-radius:5px;background:#fffdf9;padding:23px;text-decoration:none;display:block}.lesson-card:hover{border-color:#9eae94;background:#f1f3e8}.lesson-card h3{font:22px/1.5 var(--serif);margin:17px 0 10px}.lesson-card h3 span{float:right;font-family:var(--sans);font-size:16px;color:#8c9b81}.lesson-card p{font-size:12px;color:var(--muted);margin:0}.badges{display:flex;gap:6px;flex-wrap:wrap}.badge{font-size:9px;padding:3px 7px;border-radius:3px;border:1px solid transparent;line-height:1.5;display:inline-block;white-space:nowrap}.badge.core{background:#e9eee0;border-color:#c9d4bb;color:#3e6340}.badge.general{background:#f0eee1;color:#7b7549;border-color:#ded9c0}.badge.difficult{background:#f6e9dc;color:#966844;border-color:#e8d5ba}.badge.confusing{background:#e8edf0;color:#567789;border-color:#cbd6de}.status{color:var(--muted);font-size:10px}.reader-layout{display:grid;grid-template-columns:205px minmax(0,1fr) 181px;gap:32px;align-items:start}.is-reader #main{padding-top:30px;max-width:1510px}.directory,.reader-aside{position:sticky;top:158px;max-height:calc(100vh - 172px);overflow:auto;padding-right:9px;font-size:12px;scrollbar-width:thin}.directory{border-right:1px solid var(--line);padding-right:18px}.directory h2,.reader-aside h2{font:16px var(--serif);margin:5px 0 20px}.directory details{border-bottom:1px solid #e3e4d8;padding:10px 0}.directory summary{cursor:pointer;list-style:none;color:#6d7c67;font-size:12px;display:flex;gap:12px}.directory summary span{color:#9da992;font:12px Georgia,serif;margin-top:5px}.directory details[open]>summary{color:var(--green);font-weight:600;margin-bottom:11px}.directory a{display:block;text-decoration:none;font-size:11px;padding:7px 9px 7px 20px;color:#6a7664;line-height:1.7}.directory a[aria-current=page]{background:#e5ebdc;border-radius:3px;color:var(--green);border-left:2px solid var(--green);padding-left:18px}.directory .text-link{padding:12px 0;margin-top:15px}.reading{max-width:780px;min-width:0}.reading-head{border-bottom:1px solid var(--line);padding:5px 0 28px}.reading-head>a{text-decoration:none}.reading-head .badges{margin-top:17px}.reading h1{font-size:34px;margin:15px 0 13px}.reading-mode{font-size:11px;color:var(--muted)}.lesson-section{padding:28px 0;border-bottom:1px solid var(--line);scroll-margin-top:155px}.section-label{font-size:11px;color:#63805a;font-weight:600;letter-spacing:.8px;margin-bottom:17px}.lesson-section h2{font-size:25px;margin-bottom:20px}.lesson-section p,.lesson-section li{font-size:14px;line-height:1.95}.lesson-section p:last-child{margin-bottom:0}.lesson-section ul{padding-left:22px}.must-list{padding:0!important;list-style:none}.must-list li{padding:7px 0 7px 25px;position:relative}.must-list li:before{content:'✓';position:absolute;left:0;color:#769469;font-size:12px}.one-sentence{padding:25px;background:#e8eddf;margin:25px 0 0;border-left:3px solid #779164;border-radius:0 4px 4px 0}.one-sentence span{font-size:10px;color:#617658}.one-sentence p{font:22px/1.7 var(--serif);margin:10px 0 0}.mechanism-chain{counter-reset:step;display:grid;gap:0}.mechanism-chain>div{display:grid;grid-template-columns:34px minmax(0,1fr);gap:14px;position:relative;padding:0 0 20px}.mechanism-chain>div:not(:last-child):before{content:'';position:absolute;left:15px;top:28px;bottom:0;border-left:1px dashed #acb99d}.mechanism-chain span{width:31px;height:31px;border:1px solid #bdcbb2;border-radius:50%;display:grid;place-items:center;font:11px Georgia,serif;color:#638151;background:#f2f4e9;position:relative}.mechanism-chain p{margin:0;padding-top:2px}.why-block{background:#f0eee4;border-radius:4px;padding:15px 18px;margin-top:10px;font-size:12px}.why-block summary{cursor:pointer;font-size:12px;font-weight:600}.why-block p{font-size:12px;margin:13px 0 0}.citations{font-size:9px;color:var(--muted);margin-top:15px;line-height:1.8}.citations a{color:#8b957d}.lab-inline{display:flex;gap:16px;align-items:center;background:#e7ece2;padding:18px;margin-top:18px;border-radius:4px;text-decoration:none}.lab-inline>span{font:30px Georgia,serif;color:#73916a}.lab-inline b{font-size:12px}.lab-inline small{display:block;font-size:10px;color:var(--muted);margin-top:3px}.table-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:4px}table{border-collapse:collapse;width:100%;min-width:470px;background:#fffdf9;text-align:left;font-size:12px}th,td{padding:14px 15px;border-bottom:1px solid #e1e4d6;vertical-align:top;line-height:1.8}th{background:#e9eddf;font-weight:600}tr:last-child td{border-bottom:0}td:first-child{color:#506746;min-width:88px}caption{text-align:left;padding:12px}.version-note{padding:18px 20px;background:#f2ecdf;border-left:2px solid #b19056;border-radius:0 4px 4px 0;margin-top:20px}.version-note b{font-size:12px;color:#8a6a33}.version-note p{font-size:12px;line-height:1.9;margin:8px 0}.version-note a{font-size:11px}.version-note small{display:block;font-size:9px;color:#8f8b74;margin-top:8px}.reading-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px}.reading-actions small{font-size:10px;color:var(--muted);width:100%}.reader-aside{border-left:1px solid var(--line);padding-left:20px;overflow-wrap:anywhere}.reader-aside .eyebrow{font-size:8px;margin-top:7px}.reader-aside h2{margin-top:12px}.reader-aside>a{display:block;text-decoration:none;font-size:11px;padding:5px 0;color:#7a8773}.aside-priority{margin:20px 0;padding:16px 13px;background:#e9eddf;border-radius:4px}.aside-priority b{font-size:10px}.aside-priority p{font-size:10px;line-height:2;color:#78876b;margin:9px 0 0}.reader-aside .text-button{display:block;margin:10px 0}.source-list{list-style:none;margin:0;padding:0!important}.source-list li{border-bottom:1px solid var(--line);padding:11px 0;scroll-margin-top:165px}.source-list li:last-child{border:0}.source-list strong,.source-list span{display:block;font-size:11px;line-height:1.9}.source-list span{color:var(--muted);font-size:10px}.lesson-pagination{margin-top:25px;font-size:12px}.card{padding:25px;border:1px solid var(--line);background:var(--sheet);border-radius:5px}.quick-points{margin-top:24px}.quick-points h2{font-size:21px}.quick-points li{font-size:13px;padding:3px 0}.review-strip{margin:30px 0 0;border:1px solid var(--line);background:#e9ede0;border-radius:5px;padding:22px;display:grid;grid-template-columns:1fr 1fr;gap:20px}.review-strip p{font-size:12px;color:var(--muted);margin:8px 0 0}.review-links{display:flex;gap:9px;align-items:center;flex-wrap:wrap}.review-links a{font-size:10px;border:1px solid #bfcab4;border-radius:3px;padding:5px 10px;text-decoration:none}.practice-list{max-width:900px;margin:0 auto}.question{margin:18px 0;padding:25px}.question h3{font-size:16px;line-height:1.9;margin:20px 0}.question .eyebrow{font-size:9px;letter-spacing:.5px}.question fieldset{margin:0 0 22px;padding:0;border:0;display:grid;gap:9px}.option{display:flex;align-items:baseline;gap:10px;cursor:pointer;border:1px solid var(--line);padding:12px;border-radius:4px;font-size:12px}.option input{accent-color:var(--green)}.option.selected{border-color:#6f8b5f;background:#edf1e4}.letter{font:12px Georgia,serif;color:#758b68}.option>span:last-child{flex:1}.answer-label{display:block;font-size:11px;color:var(--muted);margin:14px 0 8px}textarea{display:block;width:100%;padding:15px;background:#fffef9;border:1px solid #cdd2c0;border-radius:4px;resize:vertical;min-height:120px;font-size:13px;line-height:1.9;margin-bottom:14px}.answer-panel{padding:20px;border-radius:4px;background:#eaf0e2;margin-top:20px;font-size:12px}.answer-panel>strong{font-size:13px}.answer-panel p{font-size:12px;line-height:1.9;margin:12px 0}.answer-panel details{margin-top:18px;font-size:10px}.answer-panel .text-link{margin-top:18px}.checkline{display:flex;gap:10px;align-items:baseline;font-size:12px;line-height:1.9;margin:14px 0;cursor:pointer}.checkline input{accent-color:var(--green);flex-shrink:0}.notes-layout{display:grid;grid-template-columns:1.7fr 1fr;gap:28px}.note-pad>label{font-size:12px;margin-right:15px}.note-pad h2{margin-top:25px}.note-pad textarea{min-height:360px;background:repeating-linear-gradient(transparent 0,transparent 35px,#e8e9df 36px),#fffef9;line-height:36px;background-origin:content-box;padding-top:8px}.backup-card h2{font-size:23px}.backup-card p{font-size:12px;color:var(--muted)}.backup-card button{margin-bottom:14px;display:flex}.file-label{display:block;font-size:11px;margin-top:15px;color:#63795b}.file-label input{width:100%;font-size:10px;margin-top:9px}.backup-card details{font-size:11px}.backup-card details a{display:block}.source-intro .card h2{font-size:22px}.source-intro p{font-size:12px}.updates-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}.updates-grid .version-note{margin:0}.source-license{margin-top:28px;font-size:12px}.source-license h2{font-size:23px}.notice{background:#f1ebdd;border-left:2px solid var(--gold);padding:14px 18px;margin-bottom:20px;font-size:12px}.empty{text-align:center;border:1px dashed var(--line);padding:50px 20px;color:var(--muted);font-size:13px}.migration-banner{max-width:1356px;margin:20px auto 0;background:#e9eee0;border:1px solid #becbb3;border-radius:4px;padding:15px 20px;display:flex;gap:20px;align-items:center;justify-content:space-between;font-size:12px}.migration-banner span{display:block;font-size:11px;color:var(--muted)}.storage-warning{padding:10px;background:#f6dfd3;color:#8c4530;text-align:center;font-size:12px}.toast{position:fixed;bottom:26px;left:50%;transform:translateX(-50%);z-index:80;max-width:90vw;padding:12px 22px;background:#234d41;color:#fff;border-radius:5px;font-size:12px;box-shadow:0 6px 20px #132b2430}.search-wrap #search-results{position:absolute;left:0;right:0;top:44px;background:var(--sheet);border:1px solid #b6c2a8;border-radius:4px;box-shadow:0 10px 30px #1a321e16;max-height:65vh;overflow:auto;z-index:40;min-width:330px}.search-head{padding:14px 17px;font-size:10px;color:var(--muted);background:#ebeee1}.search-wrap #search-results a{display:block;padding:12px 17px;border-top:1px solid #e5e7db;text-decoration:none}.search-wrap #search-results strong{display:block;font-size:12px}.search-wrap #search-results span{display:block;font-size:10px;color:var(--muted)}.search-wrap #search-results small{font-size:9px;color:#849478}.search-wrap #search-results p{padding:15px;font-size:12px}.mobile-only{display:none!important}.lab-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.lab-tile{padding:28px;border:1px solid var(--line);background:#fffef9;border-radius:5px;min-height:185px;text-decoration:none}.lab-tile:hover{background:#e9eee0}.lab-tile h2{font-size:24px;margin:16px 0 14px}.lab-tile h2 span{font-size:18px;float:right;color:#8d9e81}.lab-tile p{font-size:12px;color:var(--muted);margin:0}.lab-header{padding:30px 0 22px}.lab-header>a{font-size:11px}.lab-header h1{font-size:32px;margin:14px 0 5px}.lab-header p{font-size:13px;color:var(--muted);margin:0}.lab-shell{background:var(--sheet);border:1px solid var(--line);border-radius:6px;padding:28px}.lab-tools{display:flex;gap:12px;flex-wrap:wrap;align-items:center;margin-bottom:26px}.lab-tools label{font-size:11px;display:flex;gap:10px;align-items:center}.two-col{display:grid;grid-template-columns:1.1fr 1fr;gap:28px;align-items:start}.source-intro{margin-bottom:35px}.lab-explain{padding:25px 28px;background:#eef0e6;border-radius:4px;margin-top:25px}.two-col>.lab-explain{margin-top:0}.lab-explain h3{font:24px/1.65 var(--serif);margin:8px 0 14px}.lab-explain p,.lab-explain li{font-size:13px;line-height:1.9}.lab-explain a{font-size:12px}.lab-explain .small{font-size:10px}.lab-explain ol{padding-left:20px}.scroll-figure{overflow-x:auto;border:1px solid #e6dacf;border-radius:4px;max-width:100%}.ecg-svg{display:block;width:100%;min-width:820px}.two-col svg,.reentry-figure svg{width:100%;height:auto;display:block}.reentry-figure{max-width:800px;margin:auto}.lab-shell>h3{font:25px var(--serif)}#legacy-lab{border:0;width:100%;height:1250px;background:var(--sheet);display:block}dialog{width:94vw;max-width:1500px;border:1px solid #bdc7b0;border-radius:5px;background:var(--paper);padding:25px;max-height:95vh;overflow:auto}dialog::backdrop{background:#102a22aa}dialog h2{font-size:20px;margin:0}#zoom-body{margin-top:25px;overflow:auto}#zoom-body svg{min-width:850px;width:100%;max-height:78vh}.directory-toggle{margin-bottom:20px}@media(min-width:1600px){.reader-layout{grid-template-columns:225px minmax(0,1fr) 200px;gap:45px}.reading{max-width:810px}}@media(max-width:1150px){.header-top,.header-bottom{padding:0 25px;gap:20px}#main{padding-left:25px;padding-right:25px}.reader-layout{grid-template-columns:180px minmax(0,1fr);gap:28px}.reader-aside{display:none}.topic-card{padding:22px 17px;gap:12px}.hero-copy h1{font-size:44px}.dashboard-strip{grid-template-columns:1.2fr 40px 1fr;gap:20px}.dashboard-strip>div:last-child{grid-column:1 / -1;display:flex;align-items:center;gap:20px;border-top:1px solid var(--line);padding-top:14px}.dashboard-strip>div:last-child .eyebrow{margin-right:auto}.site-footer{margin:0 25px}.lab-grid{grid-template-columns:repeat(2,1fr)}.migration-banner{margin-left:25px;margin-right:25px}}@media(max-width:800px){.header-top{height:auto;min-height:115px;display:grid;grid-template-columns:1fr auto;gap:14px;padding-top:15px;padding-bottom:14px}.brand{font-size:16px}.brand small{font-size:7px}.brand-mark{width:32px;height:32px;font-size:25px}.search-wrap{grid-row:2;grid-column:1 / -1;max-width:none;width:100%}.search-wrap input{font-size:12px;padding:6px 0}.mode-switch button{font-size:10px;padding:6px 9px}.header-bottom{padding:0 23px;height:45px;overflow-x:auto}.header-bottom nav{gap:26px;white-space:nowrap}.header-bottom nav a{font-size:12px}.edition{display:none}.home-hero{gap:0;min-height:420px;grid-template-columns:1.1fr .9fr}.hero-copy{padding-top:35px}.hero-copy h1{font-size:35px}.hero-anatomy{padding:25px 0 60px}.hero-anatomy img{height:265px;max-width:100%}.hero-actions .text-link{font-size:10px}.hero-meta{gap:19px;margin-top:28px;font-size:20px}.hero-meta small{font-size:8px}.specimen-label{left:0;top:25px;font-size:7px}.anatomy-caption{left:0;right:0;bottom:36px;display:block;font-size:9px}.anatomy-caption a{display:block;margin-top:5px}.hero-copy p{font-size:11px}.hero-actions{gap:12px}.primary,.secondary{font-size:11px;padding:10px 14px}.topic-grid{grid-template-columns:repeat(2,1fr)}.topic-card{min-height:180px}.topic-card h3{font-size:21px}.topic-card .eyebrow{font-size:8px;letter-spacing:.5px}.topic-card p{font-size:11px}.three-col{gap:20px}.reader-layout{grid-template-columns:minmax(0,1fr)}.reading{max-width:740px;margin:auto;width:100%}.directory{display:none}.mobile-only{display:inline-flex!important}.directory-open .directory{display:block;position:fixed;top:0;left:0;bottom:0;height:100vh;max-height:none;width:300px;background:var(--paper);z-index:60;padding:25px;box-shadow:0 0 0 100vw #112b2266}.directory-open .directory .mobile-only{font-size:12px}.directory details summary{font-size:14px}.directory a{font-size:12px}.directory-toggle{margin:0 0 20px}.is-reader #main{padding-top:20px}.lesson-grid{gap:14px}.lesson-card{padding:18px}.lesson-card h3{font-size:21px}.lesson-card .row{gap:7px}.lesson-card .status{width:100%}.page-head h1{font-size:30px}.chapter-number{font-size:60px}.notes-layout{grid-template-columns:1fr}.filterbar{padding:12px;gap:10px}.filterbar small{margin-left:0;display:block;flex-basis:100%}.review-strip{grid-template-columns:1fr}.lab-shell{padding:18px}.two-col{grid-template-columns:1fr}.two-col>.lab-explain{margin:0}.lab-tools{gap:9px}.lab-tools label{width:100%;justify-content:space-between}.updates-grid{grid-template-columns:1fr}.site-footer{gap:15px}.site-footer span:last-child{margin-left:0;flex-basis:100%}.migration-banner{margin-left:20px;margin-right:20px;align-items:start}.migration-banner .secondary{white-space:nowrap}}@media(max-width:520px){#main{padding:0 20px 40px}.header-top{padding-left:20px;padding-right:20px;gap:10px}.header-bottom{padding:0 20px}.header-bottom nav{gap:23px}.brand{font-size:14px;letter-spacing:.5px;gap:8px}.brand small{letter-spacing:1.2px;font-size:6px}.brand-mark{width:29px;height:29px;font-size:23px}.mode-switch{padding:3px}.mode-switch button{font-size:9px;padding:6px 7px}.home-hero{grid-template-columns:1fr;min-height:0;padding-bottom:10px}.hero-copy{padding:30px 0 10px}.hero-copy .eyebrow{font-size:8px;letter-spacing:1px}.hero-copy h1{font-size:39px;line-height:1.5;margin-top:14px}.hero-copy p{font-size:12px}.hero-anatomy{height:275px;padding:10px 20px 30px}.hero-anatomy img{height:235px}.specimen-label{left:4px;top:18px;font-size:8px}.anatomy-caption{bottom:10px;left:0;right:0;display:flex;align-items:center;justify-content:space-between}.anatomy-caption a{margin:0;font-size:9px}.hero-meta{margin-top:25px;gap:25px}.hero-actions{margin-top:20px}.dashboard-strip{grid-template-columns:1fr 38px;gap:16px;padding:22px 0;margin-bottom:30px}.dashboard-strip>div:nth-last-child(2){grid-column:1 / -1;border-top:1px solid var(--line);padding-top:14px}.dashboard-strip>div:last-child{display:block}.dashboard-strip>div:last-child h3{font-size:13px}.section-heading{align-items:start;margin-bottom:18px}.section-heading h2{font-size:24px}.section-heading>a{font-size:10px;margin-top:12px}.topic-grid{grid-template-columns:1fr}.topic-card{min-height:0;padding:22px 20px;gap:23px}.topic-card>div{flex:1}.topic-card h3{font-size:24px}.topic-card p{font-size:12px}.topic-card .eyebrow{font-size:9px}.topic-index{font-size:28px}.topic-card small{font-size:10px}.study-method{padding:24px;margin-top:25px}.study-method h2{font-size:24px}.three-col{grid-template-columns:1fr;gap:24px}.three-col b{margin-bottom:6px}.page-head{padding:30px 0 22px;align-items:start}.page-head h1{font-size:28px}.page-head p{font-size:12px}.page-head .chapter-number{font-size:44px;padding-top:27px}.lesson-grid{grid-template-columns:1fr}.topic-section .section-heading{display:block}.topic-section .section-heading .muted{display:block;margin-top:8px}.lesson-card h3{font-size:23px}.filterbar label{flex-wrap:wrap}.filterbar .small{width:100%}.filterbar select{font-size:11px}.reading h1{font-size:30px}.one-sentence{padding:21px}.one-sentence p{font-size:22px}.lesson-section{padding:25px 0;scroll-margin-top:180px}.lesson-section p,.lesson-section li{font-size:14px}.question{padding:19px 15px}.question h3{font-size:15px}.option{padding:10px;gap:8px;font-size:12px}.question .row .status{display:block}.question .eyebrow{font-size:9px}.answer-panel{padding:17px 14px}.version-note{padding:16px}.card.note-pad{padding:22px 17px}.note-pad select{margin-top:10px;width:100%}.backup-card{padding:22px}.source-list li{scroll-margin-top:185px}.citations{font-size:9px}.site-footer{margin-left:20px;margin-right:20px;font-size:9px;gap:15px}.lab-grid{grid-template-columns:1fr;gap:14px}.lab-tile{padding:24px;min-height:165px}.lab-header h1{font-size:28px}.lab-header p{font-size:12px}.lab-shell{padding:15px 12px}.lab-tools .secondary,.lab-tools .primary{padding:8px 10px;font-size:10px}.lab-tools select{font-size:11px}.lab-explain{padding:22px 18px}.lab-explain h3{font-size:23px}.migration-banner{padding:14px;gap:12px;flex-wrap:wrap}.search-wrap #search-results{min-width:0}.mechanism-chain>div{gap:11px}.updates-grid .version-note p{font-size:12px}dialog{padding:17px}dialog h2{font-size:17px}.notes-layout{gap:20px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important;transition:none!important}}@media print{.site-header,.site-footer,.directory,.reader-aside,.reading-actions,.directory-toggle,.toast,#migration,.lab-inline{display:none!important}#main{padding:0;max-width:none}.reader-layout{display:block}.reading{max-width:none}.lesson-section{break-inside:avoid}.question{break-inside:avoid}.page-head{padding:10px 0}body{background:white;color:black}.table-scroll{overflow:visible}table{min-width:0}.source-list{font-size:10px}.version-note{border:1px solid #ccc}}

.aside-sources{border-top:1px solid var(--line);padding-top:15px;margin-top:15px}.aside-sources b{display:block;font-size:11px;margin-bottom:8px}.aside-sources a{display:block;font-size:10px;color:#728568;padding:3px 0;text-decoration:none}.aside-sources small{display:block;font-size:9px;color:var(--muted);line-height:2;margin-top:8px}