:root{
  --bg:#080b12;
  --surface:#0d121d;
  --card:#111827;
  --card-soft:#151d2b;
  --ink-strong:#f8fafc;
  --ink:#d8e1ee;
  --ink-soft:#9aa8bb;
  --ink-faint:#708096;
  --rule:rgba(148,163,184,.15);
  --rule-strong:rgba(148,163,184,.28);
  --accent:#4ade80;
  --accent-strong:#22c55e;
  --accent-soft:#86efac;
  --accent-fade:rgba(34,197,94,.11);
  --blue:#60a5fa;
  --amber:#fbbf24;
  --red:#fb7185;
  --nav-h:70px;
  --toc-w:286px;
  color-scheme:dark;
}
html[data-wgo-theme="light"]{
  --bg:#f4f7fb;
  --surface:#ffffff;
  --card:#ffffff;
  --card-soft:#f7f9fc;
  --ink-strong:#101828;
  --ink:#344054;
  --ink-soft:#667085;
  --ink-faint:#98a2b3;
  --rule:rgba(15,23,42,.10);
  --rule-strong:rgba(15,23,42,.18);
  --accent:#169c50;
  --accent-strong:#08783b;
  --accent-soft:#15803d;
  --accent-fade:rgba(22,156,80,.09);
  color-scheme:light;
}
*{box-sizing:border-box}
html,body{width:100%;height:100%;margin:0}
html{scroll-behavior:smooth}
body{
  overflow:hidden;background:var(--bg);color:var(--ink);
  font:400 15px/1.68 Inter,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  -webkit-font-smoothing:antialiased;
}
button,input,textarea{font:inherit}
button,a{-webkit-tap-highlight-color:transparent}
a{color:inherit}
#topnav{
  position:relative;z-index:40;height:var(--nav-h);display:flex;align-items:center;gap:8px;
  padding:10px 18px;border-bottom:1px solid var(--rule);
  background:color-mix(in srgb,var(--surface) 90%,transparent);
  backdrop-filter:blur(18px);-webkit-backdrop-filter:blur(18px);
}
.nav-back,.nav-btn{
  min-height:38px;display:inline-flex;align-items:center;justify-content:center;gap:7px;
  border:1px solid transparent;border-radius:10px;padding:0 13px;background:transparent;
  color:var(--ink-soft);font-weight:650;font-size:13px;text-decoration:none;cursor:pointer;
  transition:background .16s ease,color .16s ease,border-color .16s ease,transform .16s ease;
}
.nav-back{border-color:var(--rule);padding:0 11px}
.nav-btn:hover,.nav-back:hover{background:var(--accent-fade);color:var(--ink-strong);transform:translateY(-1px)}
.nav-btn.active{background:var(--accent-fade);border-color:color-mix(in srgb,var(--accent) 38%,transparent);color:var(--accent-soft)}
.brand{min-width:190px;margin:0 8px 0 2px}
.brand strong{display:block;color:var(--ink-strong);font:600 19px/1.05 "Fraunces",Georgia,serif;letter-spacing:-.015em}
.brand small{display:block;margin-top:4px;color:var(--ink-faint);font-size:10px;font-weight:750;letter-spacing:.12em;text-transform:uppercase}
.nav-spacer{flex:1}
#search-wrap{position:relative;width:min(310px,25vw)}
#search-input{
  width:100%;height:40px;border:1px solid var(--rule);border-radius:11px;padding:0 38px 0 38px;
  background:var(--card);color:var(--ink-strong);outline:none;
}
#search-input::placeholder{color:var(--ink-faint)}
#search-wrap:before{
  content:"";position:absolute;left:13px;top:11px;width:16px;height:16px;border:2px solid var(--ink-faint);
  border-radius:50%;pointer-events:none;
}
#search-wrap:after{
  content:"";position:absolute;left:27px;top:26px;width:7px;height:2px;border-radius:2px;
  background:var(--ink-faint);transform:rotate(45deg);pointer-events:none;
}
#search-input:focus{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-fade)}
.search-key{position:absolute;right:10px;top:10px;color:var(--ink-faint);font-size:11px;pointer-events:none}
#search-results{
  display:none;position:fixed;z-index:100;top:60px;right:74px;width:min(430px,calc(100vw - 24px));
  max-height:min(520px,70vh);overflow:auto;padding:7px;border:1px solid var(--rule-strong);
  border-radius:13px;background:var(--surface);box-shadow:0 22px 60px rgba(0,0,0,.28);
}
#search-results.open{display:block}
.sr-item{padding:10px 11px;border-radius:8px;color:var(--ink);cursor:pointer}
.sr-item:hover,.sr-item.kbd{background:var(--accent-fade);color:var(--ink-strong)}
.sr-parent{margin-bottom:2px;color:var(--accent-soft);font-size:10px;font-weight:800;letter-spacing:.08em;text-transform:uppercase}
.sr-empty{padding:16px;color:var(--ink-faint);text-align:center}
.status-pill{
  display:inline-flex;align-items:center;gap:7px;height:36px;padding:0 11px;border:1px solid var(--rule);
  border-radius:999px;color:var(--ink-soft);font-size:11px;font-weight:700;white-space:nowrap;
}
.status-pill:before{content:"";width:7px;height:7px;border-radius:50%;background:var(--accent);box-shadow:0 0 0 4px var(--accent-fade)}
.page{height:calc(100dvh - var(--nav-h));display:none;min-height:0}
.page.active{display:flex}
.toc{
  position:relative;width:var(--toc-w);flex:0 0 var(--toc-w);overflow:auto;padding:24px 16px 60px;
  border-right:1px solid var(--rule);background:var(--surface);scrollbar-width:thin;
}
.toc h2{
  margin:0 10px 15px;padding-bottom:13px;border-bottom:1px solid var(--rule);
  color:var(--accent-soft);font-size:11px;font-weight:850;letter-spacing:.15em;text-transform:uppercase;
}
.toc a{
  position:relative;display:block;margin:2px 0;padding:9px 10px 9px 32px;border:1px solid transparent;
  border-radius:9px;color:var(--ink-soft);font-size:12.5px;line-height:1.38;text-decoration:none;
}
.toc a:before{
  content:"";position:absolute;left:11px;top:14px;width:7px;height:7px;border-radius:50%;
  background:var(--ink-faint);box-shadow:0 0 0 4px var(--surface);
}
.toc a:after{
  content:"";position:absolute;left:14px;top:25px;bottom:-13px;width:1px;background:var(--rule);
}
.toc a:last-child:after{display:none}
.toc a:hover{color:var(--ink-strong);background:var(--accent-fade)}
.toc a.active,.toc a.study-active{border-color:color-mix(in srgb,var(--accent) 25%,transparent);background:var(--accent-fade);color:var(--ink-strong)}
.toc a.active:before,.toc a.study-active:before{background:var(--accent)}
.notes-main{position:relative;flex:1;min-width:0;overflow:auto;padding:38px clamp(24px,5vw,78px) 110px;scrollbar-width:thin}
.notes-shell{width:min(1100px,100%);margin:0 auto}
.toc-toggle{
  position:fixed;top:calc(var(--nav-h) + 10px);left:var(--toc-w);z-index:40;
  width:36px;height:36px;display:flex;align-items:center;justify-content:center;
  border-radius:10px;border:1px solid var(--rule-strong);background:var(--card);
  color:var(--ink-soft);cursor:pointer;padding:0;font-size:0;
  transition:left .28s cubic-bezier(.2,.8,.2,1),background .16s ease,color .16s ease,transform .16s ease;
}
.page.toc-collapsed .toc{display:none}
.page.toc-collapsed .toc-toggle{left:6px}
.ai-note{
  margin:0 auto 24px;padding:13px 16px;border:1px solid color-mix(in srgb,var(--blue) 26%,transparent);
  border-radius:12px;background:color-mix(in srgb,var(--blue) 8%,transparent);color:var(--ink-soft);
  font-size:12.5px;line-height:1.55;
}
.hero{
  position:relative;overflow:hidden;margin-bottom:24px;padding:40px clamp(26px,5vw,58px);
  border:1px solid var(--rule);border-radius:22px;background:var(--card);
}
.hero:after{
  content:"";position:absolute;right:-100px;top:-130px;width:340px;height:340px;border-radius:50%;
  background:radial-gradient(circle,var(--accent-fade),transparent 66%);pointer-events:none;
}
.eyebrow{color:var(--accent-soft);font-size:11px;font-weight:850;letter-spacing:.16em;text-transform:uppercase}
.hero h1{margin:9px 0 11px;color:var(--ink-strong);font:600 clamp(34px,5vw,58px)/1.04 "Fraunces",Georgia,serif;letter-spacing:-.035em}
.hero .lead{max-width:800px;margin:0;color:var(--ink-soft);font-size:15.5px;line-height:1.7}
.badges{display:flex;flex-wrap:wrap;gap:8px;margin-top:21px}
.badge{padding:6px 10px;border:1px solid var(--rule);border-radius:999px;background:var(--card-soft);color:var(--ink-soft);font-size:11px;font-weight:700}
.topic{
  margin:0 0 22px;padding:clamp(23px,4vw,38px);border:1px solid var(--rule);border-radius:18px;
  background:var(--card);scroll-margin-top:24px;box-shadow:0 8px 24px rgba(0,0,0,.035);
}
.topic>h2{display:flex;align-items:flex-start;gap:13px;margin:0;color:var(--ink-strong);font:600 clamp(25px,3vw,34px)/1.12 "Fraunces",Georgia,serif;letter-spacing:-.025em}
.num{
  min-width:42px;height:42px;display:inline-grid;place-items:center;border-radius:11px;
  background:linear-gradient(135deg,var(--accent-strong),#0f8f67);color:#fff;
  font:800 13px/1 Inter,sans-serif;letter-spacing:0;
}
.topic-sub{margin:10px 0 24px;color:var(--ink-soft);font-size:14px;line-height:1.65}
.topic-focus{display:flex;align-items:flex-start;gap:11px;margin:-5px 0 23px;padding:10px 12px;border:1px solid var(--rule);border-radius:11px;background:var(--card-soft)}
.topic-focus-label{flex:0 0 auto;padding-top:3px;color:var(--ink-faint);font-size:10px;font-weight:850;letter-spacing:.09em;text-transform:uppercase}
.topic-focus-tags{display:flex;flex-wrap:wrap;gap:6px}
.topic-focus-tags span{padding:3px 7px;border-radius:999px;background:var(--accent-fade);color:var(--accent-soft);font-size:10.5px;font-weight:700;line-height:1.3}
.topic h3{margin:30px 0 10px;color:var(--ink-strong);font-size:18px;line-height:1.3}
.topic h3:first-of-type{margin-top:18px}
.topic p{margin:8px 0;color:var(--ink);line-height:1.72}
.topic ul,.topic ol{margin:10px 0;padding-left:22px}
.topic li{margin:7px 0;color:var(--ink)}
.topic strong{color:var(--ink-strong)}
.topic table{width:100%;margin:15px 0;border-collapse:separate;border-spacing:0;border:1px solid var(--rule);border-radius:11px;overflow:hidden;font-size:13px}
.topic th,.topic td{padding:10px 12px;border-right:1px solid var(--rule);border-bottom:1px solid var(--rule);text-align:left;vertical-align:top}
.topic th{background:var(--card-soft);color:var(--ink-strong);font-weight:750}
.topic td{color:var(--ink)}
.topic tr:last-child td{border-bottom:0}
.topic th:last-child,.topic td:last-child{border-right:0}
.concept-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:11px;margin:17px 0}
.source-depth{margin:22px 0 8px;padding:1px 16px 15px;border:1px solid color-mix(in srgb,var(--accent) 28%,var(--rule));border-radius:13px;background:linear-gradient(135deg,color-mix(in srgb,var(--accent) 7%,var(--card-soft)),var(--card-soft))}
.source-depth h3{color:var(--accent-soft)}
.board-depth{margin:20px 0 10px;padding:1px 16px 15px;border-left:3px solid var(--accent);background:color-mix(in srgb,var(--accent) 4%,transparent)}
.board-depth h3{color:var(--ink-strong)}
.study-figure{margin:18px 0;padding:14px;border:1px solid var(--rule);border-radius:12px;background:var(--card-soft)}
.study-figure svg{display:block;width:100%;height:auto;color:var(--accent)}
.study-figure rect{fill:color-mix(in srgb,var(--accent) 10%,var(--card));stroke:currentColor;stroke-width:1.4}
.study-figure path{fill:none;stroke:currentColor;stroke-width:1.8}
.study-figure marker path{fill:currentColor;stroke:none}
.study-figure text{fill:var(--ink-strong);font:700 13px Inter,Arial,sans-serif}
.study-figure figcaption{margin-top:10px;color:var(--ink-soft);font-size:11px;line-height:1.5;text-align:center}
@media(max-width:720px){.board-depth{padding:1px 12px 13px}.study-figure{padding:10px;overflow-x:auto}.study-figure svg{min-width:720px}}
.concept{padding:15px;border:1px solid var(--rule);border-radius:12px;background:var(--card-soft)}
.concept b{display:block;margin-bottom:5px;color:var(--accent-soft);font-size:12px;text-transform:uppercase;letter-spacing:.07em}
.concept p{margin:0;font-size:13px;line-height:1.55}
.process{display:grid;grid-template-columns:repeat(auto-fit,minmax(130px,1fr));gap:9px;margin:17px 0}
.process-step{position:relative;padding:14px;border:1px solid var(--rule);border-radius:11px;background:var(--card-soft)}
.process-step span{display:block;margin-bottom:4px;color:var(--accent-soft);font-size:10px;font-weight:850;letter-spacing:.1em;text-transform:uppercase}
.process-step p{margin:0;font-size:12.5px;line-height:1.5}
.formula,.equation,.tip,.warning,.method{
  margin:17px 0;padding:14px 16px;border-left:3px solid var(--accent);border-radius:0 11px 11px 0;
  background:var(--accent-fade);color:var(--ink);
}
.formula,.equation{max-width:100%;overflow-x:auto;overflow-y:hidden;border-color:var(--blue);background:color-mix(in srgb,var(--blue) 8%,transparent);font-family:"STIX Two Text","Times New Roman",serif;font-size:17px}
.tip{border-color:var(--amber);background:color-mix(in srgb,var(--amber) 8%,transparent)}
.warning{border-color:var(--red);background:color-mix(in srgb,var(--red) 8%,transparent)}
.method{border-color:var(--accent)}
.formula b,.equation b,.tip b,.warning b,.method b{color:var(--ink-strong)}
.recall{margin-top:20px;border:1px solid var(--rule);border-radius:11px;background:var(--card-soft)}
.recall summary{padding:12px 14px;color:var(--ink-strong);font-weight:750;cursor:pointer}
.recall div{padding:0 14px 14px;color:var(--ink-soft)}
.source-figure{
  width:min(100%,720px);margin:18px auto;padding:15px;border:1px solid var(--rule);border-radius:14px;background:#fff;overflow:hidden;
}
.source-figure img{display:block;width:auto;max-width:100%;max-height:640px;margin:0 auto;object-fit:contain}
.source-figure img[src*="aqa-human-heart"]{max-width:min(100%,640px)}
.source-figure img[src*="edexcel-topic1-heart"]{max-width:min(100%,470px)}
.source-figure img[src*="double-circulation-heart"]{max-width:min(100%,760px)}
.source-figure figcaption{margin-top:10px;color:#596273;font-size:11px;line-height:1.5;text-align:center}
#to-top{
  position:fixed;z-index:35;right:18px;bottom:25px;width:42px;height:42px;border:1px solid var(--rule-strong);
  border-radius:12px;background:var(--card);color:var(--ink-strong);cursor:pointer;opacity:0;pointer-events:none;
  transition:opacity .18s,transform .18s;box-shadow:0 12px 30px rgba(0,0,0,.18);
}
#to-top.show{opacity:1;pointer-events:auto}
#to-top:hover{transform:translateY(-2px)}
/* Tutor */
#tutor-page{min-height:0}
.tutor-shell{width:100%;display:flex;min-height:0}
#sidebar{
  width:270px;flex:0 0 270px;display:flex;flex-direction:column;border-right:1px solid var(--rule);background:var(--surface);
  transition:width .26s cubic-bezier(.2,.8,.2,1),flex-basis .26s cubic-bezier(.2,.8,.2,1);
}
#sidebar.collapsed{width:0;flex-basis:0;overflow:hidden;border:0}
.sidebar-head{padding:15px;border-bottom:1px solid var(--rule)}
.new-chat-btn{width:100%;height:40px;border:1px solid color-mix(in srgb,var(--accent) 38%,transparent);border-radius:10px;background:var(--accent-fade);color:var(--ink-strong);font-weight:750;cursor:pointer}
#chat-list{flex:1;overflow:auto;padding:8px}
.chat-item{display:flex;align-items:center;gap:8px;margin:2px 0;padding:9px;border-radius:8px;color:var(--ink-soft);font-size:12px;cursor:pointer}
.chat-item:hover,.chat-item.active{background:var(--accent-fade);color:var(--ink-strong)}
.chat-title{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.chat-del{border:0;background:transparent;color:var(--ink-faint);font-size:17px;cursor:pointer}
.chat-del:hover{color:var(--red)}
#main-pane{min-width:0;flex:1;display:flex;flex-direction:column}
.chat-header{height:58px;display:flex;align-items:center;padding:9px 17px;border-bottom:1px solid var(--rule);background:var(--surface)}
.chat-header h1{display:flex;align-items:center;gap:8px;margin:0;color:var(--ink-strong);font-size:14px}
.chat-header h1:before{content:"";width:8px;height:8px;border-radius:50%;background:var(--accent);box-shadow:0 0 0 4px var(--accent-fade)}
.sidebar-toggle{width:34px;height:34px;margin-right:11px;border:1px solid var(--rule);border-radius:9px;background:var(--card);color:var(--ink-soft);cursor:pointer}
.sidebar-toggle:before{content:"☰";font-size:16px;line-height:1}
.sidebar-toggle:hover{border-color:color-mix(in srgb,var(--accent) 38%,transparent);background:var(--accent-fade);color:var(--ink-strong)}
#msgs{flex:1;min-height:0;overflow:auto;padding:26px clamp(13px,4vw,52px)}
.msg-wrap{width:min(100%,960px);margin:0 auto 15px}
.msg{font-size:14px;line-height:1.68}
.msg.user{width:max-content;max-width:82%;margin-left:auto;padding:10px 14px;border-radius:15px 15px 3px 15px;background:var(--accent-strong);color:#fff;white-space:pre-wrap}
.msg.bot{padding:18px;border:1px solid var(--rule);border-radius:4px 15px 15px 15px;background:var(--card);overflow-wrap:anywhere}
.msg.bot p{margin:0 0 10px}.msg.bot h2,.msg.bot h3{color:var(--ink-strong)}
.msg.bot pre{overflow:auto;padding:12px;border:1px solid var(--rule);border-radius:9px;background:var(--surface);white-space:pre-wrap}
.ai-table{width:100%;margin:12px 0;border-collapse:collapse}.ai-table th,.ai-table td{padding:9px;border:1px solid var(--rule);text-align:left}
.thinking{display:flex;align-items:center;gap:9px;color:var(--ink-soft)}
.dot-spin{width:15px;height:15px;border:2px solid var(--rule-strong);border-top-color:var(--accent);border-radius:50%;animation:spin .8s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
#composer{padding:11px clamp(12px,4vw,44px) 15px;border-top:1px solid var(--rule);background:var(--surface)}
#att-preview{width:min(100%,960px);margin:0 auto 7px;display:flex;gap:6px;flex-wrap:wrap}
.att-chip{display:flex;gap:7px;padding:5px 9px;border:1px solid var(--rule);border-radius:999px;background:var(--card);color:var(--ink-soft);font-size:11px}
.att-chip button{border:0;background:none;color:var(--ink-faint);cursor:pointer}
#input-wrap{width:min(100%,960px);margin:0 auto;display:flex;align-items:flex-end;gap:7px;padding:7px;border:1px solid var(--rule-strong);border-radius:15px;background:var(--card)}
#input-wrap:focus-within{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-fade)}
#input{flex:1;min-height:36px;max-height:180px;padding:7px;border:0;outline:0;resize:none;background:transparent;color:var(--ink-strong);line-height:1.5}
#input::placeholder{color:var(--ink-faint)}
#att-btn,#send{height:36px;display:grid;place-items:center;border-radius:10px;cursor:pointer}
#att-btn{width:36px;border:1px solid var(--rule);background:transparent;color:var(--ink-soft)}
#send{min-width:70px;border:0;padding:0 14px;background:var(--accent-strong);color:#fff;font-weight:750}
#send:disabled{opacity:.5;cursor:not-allowed}
.legal-strip{position:fixed;z-index:45;left:0;right:0;bottom:0;padding:4px 12px;background:color-mix(in srgb,var(--surface) 92%,transparent);border-top:1px solid var(--rule);color:var(--ink-faint);font-size:9px;text-align:center}
@media(max-width:1040px){
  .brand{min-width:auto}.brand small{display:none}.status-pill{display:none}
  #search-wrap{width:min(250px,25vw)}
}
@media(max-width:780px){
  :root{--nav-h:62px}
  body.biology-notes-page #topnav{gap:4px!important;padding:8px 4px!important}
  .brand{display:none}body.biology-notes-page #topnav .nav-back{font-size:0!important;width:38px;padding:0}.nav-back:after{content:"\2190";font-size:17px}
  body.biology-notes-page #topnav .nav-btn{padding:0 9px;font-size:11.5px!important}
  body.biology-notes-page #theme-toggle-slot,body.biology-notes-page #wgo-user-button{display:none!important}
  #search-wrap{margin-left:auto;width:40px}
  #search-input{padding:0;width:40px;color:transparent;cursor:pointer}
  #search-input::placeholder{color:transparent}
  #search-wrap:focus-within{position:absolute;left:8px;right:8px;z-index:70;width:auto}
  #search-wrap:focus-within #search-input{width:100%;padding:0 38px;color:var(--ink-strong);cursor:text}
  #search-wrap:focus-within #search-input::placeholder{color:var(--ink-faint)}
  #search-wrap:focus-within .search-key{display:block}.search-key{display:none}
  #search-results{top:58px;right:8px}
  .toc{position:fixed;z-index:60;top:var(--nav-h);bottom:0;left:0;width:min(86vw,320px);transform:translateX(-102%);transition:transform .24s ease;box-shadow:18px 0 44px rgba(0,0,0,.25)}
  .page.toc-open .toc{transform:translateX(0)}
  .notes-main{padding:22px 12px 90px}
  .toc-toggle{position:fixed;top:calc(var(--nav-h) + 10px);left:6px;z-index:40;float:none;margin:0!important;transform:none;transition:left .28s cubic-bezier(.2,.8,.2,1)}
  .page.toc-open .toc-toggle{left:min(calc(86vw + 6px),326px)}
  .hero{padding:28px 22px;border-radius:17px}.hero h1{font-size:36px}
  .topic{padding:22px 17px;border-radius:15px}.topic>h2{font-size:25px}.num{min-width:37px;height:37px}
  .topic-focus{display:block}.topic-focus-label{display:block;margin-bottom:7px;padding-top:0}
  .concept-grid{grid-template-columns:1fr}
  .topic table{display:block;overflow-x:auto;white-space:nowrap}
  #sidebar{position:absolute;z-index:50;top:0;bottom:0;left:0;width:min(84vw,300px);flex-basis:min(84vw,300px);box-shadow:18px 0 45px rgba(0,0,0,.25)}
  #sidebar.collapsed{width:0;flex-basis:0;box-shadow:none}
  #msgs{padding:18px 10px}.msg.user{max-width:92%}
  #composer{padding:9px 9px 28px}.legal-strip{display:none}
}
@media(max-width:470px){
  body.biology-notes-page #topnav .nav-btn{padding:0 6px!important;font-size:10.5px!important;white-space:nowrap}
  body.biology-notes-page #topnav .nav-btn[data-page="tutor"]{width:32px;padding:0!important;font-size:0!important}
  body.biology-notes-page #topnav .nav-btn[data-page="tutor"]:after{content:"AI";font-size:10px;font-weight:800;letter-spacing:.02em}
  .nav-btn .wide{display:none}
  .hero h1{font-size:31px}.topic-sub{font-size:13px}
  .process{grid-template-columns:1fr}
}
@media(max-width:350px){
  body.biology-notes-page #topnav .nav-btn[data-page="practicals"]{width:40px;padding:0!important;font-size:0!important}
  body.biology-notes-page #topnav .nav-btn[data-page="practicals"]:after{content:"Labs";font-size:10px;font-weight:800;letter-spacing:.01em}
}
@media print{
  body{overflow:visible;background:#fff;color:#111}
  #topnav,.toc,.toc-toggle,#tutor-page,#to-top,.legal-strip,.study-ask-btn{display:none!important}
  .page{display:block!important;height:auto}.notes-main{overflow:visible;padding:0}.notes-shell{width:100%}
  .topic,.hero{break-inside:avoid;border:1px solid #bbb;box-shadow:none}
}