:root{--onacc:#fff;--bg:#ffffff;--card:#fff;--ink:#16203a;--mut:#5d6785;--acc:#3550c8;--acc2:#7a4fd6;--soft:#eef1fb;--ok:#137a3a;--okbg:#e8f7ee;--bad:#c2341f;--badbg:#fdecea;--line:#e2e6f0;--warn:#a16207;--sh:0 1px 2px rgba(20,30,60,.06),0 4px 16px rgba(20,30,60,.06)}
[data-theme=calm]{--bg:#f3f7f4;--card:#ffffff;--ink:#1c2b24;--mut:#4d5f56;--acc:#2f6b4f;--acc2:#3f7d74;--soft:#e4eee8;--line:#d3e0d8;--ok:#1d6b3a;--okbg:#e3f3e8;--bad:#b02a1a;--badbg:#fbe9e6;--warn:#8a5300}
[data-theme=warm]{--bg:#faf6ee;--card:#fffdf8;--ink:#2e2418;--mut:#65553f;--acc:#9a4a12;--acc2:#b4562a;--soft:#f1e8d8;--line:#e6dac4;--ok:#1f6b34;--okbg:#e7f2e0;--bad:#b02a1a;--badbg:#fbe9e3;--warn:#80500a}
[data-theme=dark]{--onacc:#0f1320;--bg:#0f1320;--card:#181e2f;--ink:#e7eaf3;--mut:#9aa3bd;--acc:#7f95ff;--acc2:#b393ff;--soft:#222a40;--ok:#4ade80;--okbg:#12301f;--bad:#f87171;--badbg:#3a1717;--line:#2a3249;--warn:#fbbf24;--sh:none}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}
body{margin:0;transition:background-color .25s ease,color .25s ease;font:17px/1.65 system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;background:var(--bg);color:var(--ink)}
a{color:var(--acc)}
.side{position:fixed;top:0;left:0;bottom:0;width:248px;background:var(--card);border-right:1px solid var(--line);display:flex;flex-direction:column;z-index:40;transition:width .22s ease,transform .25s ease;overflow:hidden}
.side .brand{padding:16px 16px 12px}.brand{font-weight:800;font-size:18px;text-decoration:none;color:var(--ink);display:flex;align-items:center;gap:10px;white-space:nowrap}
.brand svg{flex:none;border-radius:10px}.subj{display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:12px;margin:0 0 22px}.subj .tile{padding:14px 16px}.subj .tile.off{opacity:.7;cursor:default}.subj .tile.cur{border-color:var(--acc);box-shadow:0 0 0 2px var(--acc) inset}
.brand i{flex:none;display:inline-grid;place-items:center;width:32px;height:32px;border-radius:10px;background:linear-gradient(135deg,var(--acc),var(--acc2));color:#fff;font-style:normal;font-size:14px}
.side nav{flex:1;overflow-y:auto;padding:6px 10px}.side nav a{display:flex;align-items:center;gap:12px;padding:11px 12px;margin:2px 0;border-radius:11px;text-decoration:none;color:var(--mut);font-weight:600;font-size:15.5px;white-space:nowrap;transition:background .15s,color .15s}
.side nav a b{flex:none;width:24px;height:24px;display:grid;place-items:center;color:inherit}.side nav a span em{font-style:normal;display:block}.side nav a span small{display:block;font-size:12px;font-weight:500;color:var(--mut);white-space:normal;line-height:1.3}.side nav a:hover{background:var(--soft);color:var(--ink)}.side nav a.on{background:var(--soft);color:var(--acc)}
.side .sep{height:1px;background:var(--line);margin:8px 6px}
.themebox{padding:12px 16px 16px;border-top:1px solid var(--line)}.themebox .lbl{margin:0 0 8px;font-size:12px}
.seg{display:flex;background:var(--soft);border-radius:10px;padding:3px;gap:3px}.seg button{flex:1;font:inherit;font-size:14px;font-weight:600;border:0;background:transparent;color:var(--mut);border-radius:8px;padding:7px;cursor:pointer}.seg button.on{background:var(--card);color:var(--ink);box-shadow:var(--sh)}
.sw{display:flex;gap:8px;margin-top:10px}.sw button{width:26px;height:26px;border-radius:50%;border:2px solid var(--card);outline:2px solid transparent;cursor:pointer;transition:transform .15s}.sw button.on{outline-color:var(--ink)}.sw button:hover{transform:scale(1.12)}
.shell{margin-left:248px;transition:margin-left .22s ease;min-height:100vh}
.top{position:sticky;top:0;z-index:20;background:color-mix(in srgb,var(--bg) 88%,transparent);backdrop-filter:blur(8px);display:flex;align-items:center;gap:10px;padding:10px 16px;padding-top:max(10px,env(safe-area-inset-top))}
.top .ttl{font-weight:700;color:var(--mut);font-size:15px}
.icon{background:var(--soft);color:var(--ink);border:0;border-radius:10px;width:42px;height:42px;font-size:18px;cursor:pointer;flex:none}
body.collapsed .side{width:68px}body.collapsed .shell{margin-left:68px}body.collapsed .side nav a span,body.collapsed .side .brand span,body.collapsed .themebox{display:none}
@media(max-width:600px){.ttl{display:none}.dots{gap:5px}.dots button{width:20px;height:20px}.top{gap:8px;padding-left:10px;padding-right:10px}}
#scrim{position:fixed;inset:0;background:rgba(10,15,30,.4);z-index:35;opacity:0;pointer-events:none;transition:opacity .2s}
@media(max-width:820px){.side{transform:translateX(-100%);width:270px;box-shadow:0 10px 40px rgba(0,0,0,.25)}.shell,body.collapsed .shell{margin-left:0}body.collapsed .side{width:270px}body.collapsed .side nav a span,body.collapsed .side .brand span{display:inline}body.collapsed .themebox{display:block}
 body.drawer .side{transform:none;visibility:visible}.side{visibility:hidden;transition:transform .25s ease,visibility 0s .25s}body.drawer .side{transition:transform .25s ease}body.drawer #scrim{opacity:1;pointer-events:auto}}
@keyframes fadeUp{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}@keyframes pop{0%{transform:scale(.98);opacity:.6}100%{transform:none;opacity:1}}
main.anim>*{animation:fadeUp .32s ease both}main.anim>*:nth-child(2){animation-delay:.03s}main.anim>*:nth-child(3){animation-delay:.06s}main.anim>*:nth-child(n+4){animation-delay:.09s}
.exp,#after>*,.reveal{animation:fadeUp .3s ease both}.opt.ok,.opt.bad{animation:pop .25s ease}
.btn,.chip,.opt,.tile,.icon{transition:transform .12s ease,background .15s,border-color .15s,box-shadow .15s}.btn:active,.chip:active,.opt:active:not(:disabled),.icon:active{transform:scale(.97)}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}}
.ai{border:1.5px solid var(--acc);border-radius:16px;padding:16px;margin:14px 0;background:var(--card)}.ai q{display:block;quotes:none;font-style:italic;border-left:3px solid var(--acc2);padding:2px 10px;margin:6px 0;color:var(--ink);background:var(--soft);border-radius:6px}
.st-met{color:var(--ok);font-weight:700}.st-partly{color:var(--warn);font-weight:700}.st-missed{color:var(--bad);font-weight:700}
.spin{display:inline-block;width:16px;height:16px;border:2px solid currentColor;border-right-color:transparent;border-radius:50%;animation:sp 0.8s linear infinite}@keyframes sp{to{transform:rotate(360deg)}}
main{max-width:1000px;margin:0 auto;padding:18px 14px 40px}
h1{font-size:28px;line-height:1.2;margin:6px 0 6px}h2{font-size:22px;margin:22px 0 10px}h3{font-size:18px}
.mut{color:var(--mut)}.small{font-size:14px}
:focus-visible{outline:3px solid var(--acc);outline-offset:2px;border-radius:6px}.card{transition:background-color .25s,border-color .25s;background:var(--card);border:1px solid var(--line);border-radius:16px;padding:18px;margin:0 0 14px;box-shadow:var(--sh)}
.hero{background:linear-gradient(135deg,var(--acc),var(--acc2));color:var(--onacc);border:0;padding:24px}.hero h1{color:var(--onacc)}.hero p{margin:4px 0;opacity:.92}
.countdown{display:inline-block;background:rgba(255,255,255,.18);padding:6px 12px;border-radius:99px;font-weight:700;margin-top:10px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(270px,1fr));gap:14px}
.tile{display:block;text-decoration:none;color:var(--ink);background:var(--card);border:1px solid var(--line);border-radius:16px;padding:18px;box-shadow:var(--sh);transition:transform .12s,border-color .12s;position:relative}
.tile:hover{transform:translateY(-2px);border-color:var(--acc)}.tile .em{font-size:30px}.tile h3{margin:6px 0 4px}.tile p{margin:0;color:var(--mut);font-size:15px}
.tile.soon{opacity:.75}.badge{display:inline-block;font-size:12px;font-weight:700;padding:3px 9px;border-radius:99px;background:var(--soft);color:var(--acc);margin-right:4px}
.badge.w{background:#fff4d6;color:#8a5a00}[data-theme=dark] .badge.w{background:#3a2e10;color:var(--warn)}
.btn{font:inherit;font-weight:700;border:0;border-radius:12px;padding:12px 20px;min-height:48px;background:var(--acc);color:var(--onacc);cursor:pointer;display:inline-flex;align-items:center;gap:8px;justify-content:center;text-decoration:none}
.btn.big{font-size:20px;padding:16px 30px;min-height:60px;width:100%;max-width:420px}
.btn.sec{background:var(--soft);color:var(--ink)}.btn.ghost{background:transparent;color:var(--acc);border:1px solid var(--line)}.btn:disabled{opacity:.45;cursor:default}
.row{display:flex;gap:10px;flex-wrap:wrap;align-items:center}
.chips{display:flex;gap:8px;flex-wrap:wrap;margin:6px 0 14px}.chip{font:inherit;font-size:15px;font-weight:600;border:1.5px solid var(--line);background:var(--card);color:var(--ink);border-radius:99px;padding:9px 16px;min-height:44px;cursor:pointer}
.chip.on{background:var(--acc);border-color:var(--acc);color:var(--onacc)}
.lbl{font-weight:700;font-size:14px;text-transform:uppercase;letter-spacing:.04em;color:var(--mut);margin-top:6px}
details{border:1px solid var(--line);border-radius:12px;padding:0 14px;margin:10px 0;background:var(--card)}details>summary{cursor:pointer;font-weight:700;padding:13px 0;min-height:44px;list-style-position:outside}
details[open]>summary{border-bottom:1px solid var(--line);margin-bottom:8px}
.tcheck{display:flex;gap:10px;align-items:flex-start;padding:8px 0;font-size:15px;cursor:pointer}.tcheck input{width:22px;height:22px;flex:none;margin-top:2px;accent-color:var(--acc)}
.bar{height:10px;background:var(--soft);border-radius:99px;overflow:hidden}.bar>div{height:100%;background:linear-gradient(90deg,var(--acc),var(--acc2));transition:width .3s}
.qhead{display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap;font-size:15px;color:var(--mut);margin:10px 0}
.stem{font-size:19px;font-weight:600;margin:6px 0 14px;white-space:pre-wrap}
.opt{display:flex;gap:12px;width:100%;text-align:left;font:inherit;font-size:17px;background:var(--card);color:var(--ink);border:2px solid var(--line);border-radius:14px;margin:9px 0;padding:14px 16px;min-height:58px;cursor:pointer;align-items:flex-start}
.opt .L{flex:none;display:grid;place-items:center;width:30px;height:30px;border-radius:50%;background:var(--soft);font-weight:800;font-size:15px}
.opt.sel{border-color:var(--acc);background:var(--soft)}.opt.sel .L{background:var(--acc);color:var(--onacc)}.opt:hover:not(:disabled){border-color:var(--acc)}.opt:disabled{cursor:default}
.opt.ok{background:var(--okbg);border-color:var(--ok)}.opt.ok .L{background:var(--ok);color:#fff}.opt.bad{background:var(--badbg);border-color:var(--bad)}.opt.bad .L{background:var(--bad);color:#fff}
.exp{border-left:5px solid var(--acc);background:var(--soft);padding:14px 16px;border-radius:12px;margin-top:12px;font-size:17px;line-height:1.65}
.flag{color:var(--warn);font-size:14px;margin-top:6px}
.stick{position:sticky;bottom:0;background:linear-gradient(transparent,var(--bg) 30%);padding:14px 0 6px}

textarea{width:100%;min-height:260px;font:inherit;font-size:17px;line-height:1.6;padding:14px;border-radius:12px;border:1.5px solid var(--line);background:var(--card);color:var(--ink);resize:vertical}
textarea:focus,select:focus{outline:2px solid var(--acc);border-color:var(--acc)}
select,input[type=search]{font:inherit;padding:10px 12px;border-radius:10px;border:1.5px solid var(--line);background:var(--card);color:var(--ink);min-height:46px}
.timer{font-variant-numeric:tabular-nums;font-weight:800;font-size:20px;padding:6px 14px;border-radius:10px;background:var(--soft)}.timer.low{background:var(--badbg);color:var(--bad)}
.list a.item{display:block;padding:14px 16px;border:1px solid var(--line);border-radius:12px;margin:8px 0;text-decoration:none;color:var(--ink);background:var(--card)}.list a.item:hover{border-color:var(--acc)}
.item .meta{font-size:13px;color:var(--mut);margin-bottom:3px}.done{color:var(--ok);font-weight:700}
.doc{font-size:17px;line-height:1.75;max-width:750px}.shorts h2{margin-top:1.8em;padding-bottom:4px;border-bottom:1px solid var(--line)}.shorts h3{margin-top:1.4em;font-size:1.12em}.shorts p{margin:.6em 0}.shorts ul{padding-left:1.2em}.shorts li{margin:.3em 0}.shortslink{margin:-6px 0 16px;font-size:15px}.shortsjump{font-size:15px}@media(max-width:600px){.shorts{font-size:16.5px;line-height:1.7}.shorts h1{font-size:1.6em}}.crumb{font-size:14px;color:var(--mut);margin:2px 0 8px}.crumb a{text-decoration:none}.crumb a:hover{text-decoration:underline}
.docwrap{display:grid;grid-template-columns:220px minmax(0,1fr);gap:22px;align-items:start}.secnav{position:sticky;top:70px;max-height:calc(100vh - 90px);overflow:auto;font-size:14px;border-left:2px solid var(--line);padding-left:4px}
.secnav a{display:block;padding:6px 10px;border-radius:8px;text-decoration:none;color:var(--mut);line-height:1.35}.secnav a:hover{background:var(--soft);color:var(--ink)}.secnav a.on{color:var(--acc);background:var(--soft);font-weight:700}
@media(max-width:1000px){.docwrap{grid-template-columns:1fr}.secnav{position:sticky;top:60px;z-index:12;display:flex;gap:6px;overflow-x:auto;border:0;background:var(--bg);padding:6px 0;max-height:none}.secnav a{white-space:nowrap;border:1px solid var(--line);border-radius:99px;padding:6px 12px}}
details.sec{border-radius:16px;margin:0 0 12px;padding:0 18px;box-shadow:var(--sh)}details.sec>summary{padding:16px 0;font-size:19px}details.sec>summary .sum{display:block;font-weight:400;font-size:14.5px;color:var(--mut);margin-top:3px;line-height:1.45}
details.sub{border:1px solid var(--line);background:var(--bg);margin:10px 0}details.sub>summary{font-size:16.5px}details.sub.model>summary::after{content:'Model answer · tap to reveal';margin-left:8px;font-size:11.5px;font-weight:700;color:var(--acc);background:var(--soft);padding:2px 8px;border-radius:99px;vertical-align:middle}details.sub.model[open]>summary::after{content:'Model answer'}
.doc blockquote{border:1px solid var(--line);border-left:5px solid var(--acc2);background:var(--soft);border-radius:12px;padding:10px 16px;margin:14px 0}
.callout{border:1px solid var(--line);border-left:5px solid var(--acc);background:var(--soft);border-radius:12px;padding:10px 16px;margin:14px 0}.callout::before{content:attr(data-k);display:block;font-size:11.5px;font-weight:800;letter-spacing:.06em;text-transform:uppercase;color:var(--acc);margin-bottom:2px}
.tw-scroll{overflow-x:auto;margin:12px 0;border:1px solid var(--line);border-radius:12px}.doc .tw-scroll table{display:table;margin:0;border:0}.doc .tw-scroll td,.doc .tw-scroll th{border:0;border-bottom:1px solid var(--line)}
mark{background:#ffe58a;color:#1a1a1a;border-radius:3px}
[id]{scroll-margin-top:80px}@media(max-width:1000px){[id]{scroll-margin-top:130px}}
.tabs{display:flex;gap:4px;overflow-x:auto;border-bottom:1px solid var(--line);margin:8px 0 16px}.tabs a{padding:10px 14px;text-decoration:none;color:var(--mut);font-weight:600;border-bottom:3px solid transparent;white-space:nowrap}.tabs a.on{color:var(--acc);border-bottom-color:var(--acc)}
.pn{display:flex;justify-content:space-between;align-items:center;gap:10px;margin:22px 0}.btn.dis{opacity:.4;pointer-events:none}
.docsec{max-width:none}.docsec h2{margin-top:0}.docsec h3{margin-top:26px;padding-top:6px;border-top:1px dashed var(--line)}
.secnav .l3{padding-left:22px;font-size:13px}.otp>summary{font-weight:700;padding:6px 10px;cursor:pointer}@media(min-width:1001px){.otp>summary{pointer-events:none;list-style:none}}
@media(max-width:1000px){.secnav{display:block;position:sticky;top:58px;background:var(--bg);z-index:12;border:1px solid var(--line);border-radius:12px;padding:0 6px}.secnav a{display:block;white-space:normal;border:0;border-radius:8px}.otp[open]{max-height:60vh;overflow:auto}}
.vb{font-size:12px;font-weight:700;color:var(--ok);background:var(--okbg);border-radius:99px;padding:1px 8px;white-space:nowrap}
.links a{font-weight:600}
@media(max-width:1000px){.tabs{flex-wrap:wrap;overflow:visible;gap:2px}.tabs a{padding:8px 10px;font-size:14.5px}}
.tabdesc{color:var(--mut);margin:-6px 0 12px;font-size:15px}
.cover{border:1px solid var(--line);border-radius:12px;padding:10px 14px;margin:0 0 16px;background:var(--soft)}.cover summary{cursor:pointer;font-size:15px;font-weight:400;line-height:1.5}.cover summary b{font-weight:700}.cover select{max-width:100%}
.mine{font-size:11px;font-weight:700;background:var(--acc);color:var(--onacc);border-radius:99px;padding:1px 8px;vertical-align:middle}
.starts{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:12px;margin-top:8px}.starts .big{display:block;padding:16px 18px;border-radius:14px;background:var(--acc);color:var(--onacc);text-decoration:none}.starts .big b{display:block;font-size:19px}.starts .big small{display:block;opacity:.9;margin-top:4px;font-size:13.5px}
.qp{display:flex;gap:10px;align-items:baseline;margin:6px 0}.ql{flex:none;font-weight:700;min-width:2.6em}.qt{flex:1}.qm{flex:none;font-size:13px;font-weight:700;color:var(--mut);white-space:nowrap}.qopts{margin:4px 0 0;padding-left:20px}
.yjump{position:sticky;top:60px;z-index:11;display:flex;flex-wrap:wrap;gap:4px;padding:8px 0;background:var(--bg)}.yjump a{padding:4px 10px;border:1px solid var(--line);border-radius:99px;text-decoration:none;font-size:14px;font-weight:600}
.mcards{display:grid;gap:12px;margin:12px 0}.mcard{border:1px solid var(--line);border-radius:12px;padding:12px 14px;background:var(--card)}.mcard h4{margin:0 0 6px}.mcard p{margin:6px 0}.ml{display:inline-block;font-weight:700;color:var(--acc);margin-right:4px}
.blank{display:inline-block;min-width:5em;border-bottom:2px solid var(--acc);color:transparent}.fillhint{color:var(--mut);font-style:normal;font-size:.92em}
#btt{position:fixed;right:18px;bottom:18px;z-index:30;opacity:0;pointer-events:none;transform:translateY(8px);transition:opacity .2s,transform .2s}#btt.show{opacity:1;pointer-events:auto;transform:none}
.dots{display:flex;gap:7px;align-items:center}.dots button{width:24px;height:24px;border-radius:50%;border:2px solid var(--line);cursor:pointer;padding:0}.dots button.on{outline:2px solid var(--acc);outline-offset:2px}
.qs{flex:1;max-width:360px}.qs input{width:100%;min-height:40px;padding:8px 12px}
.side .grp{font-size:11.5px;font-weight:800;letter-spacing:.06em;text-transform:uppercase;color:var(--mut);padding:12px 12px 4px}body.collapsed .side .grp{visibility:hidden;height:8px;padding:0}.doc table{border-collapse:collapse;width:100%;font-size:14.5px;display:block;overflow-x:auto}.doc td,.doc th{border:1px solid var(--line);padding:6px 8px;vertical-align:top;text-align:left}.doc th{background:var(--soft)}
.doc blockquote{border-left:4px solid var(--acc2);margin:10px 0;padding:4px 14px;background:var(--soft);border-radius:8px}
.doc h1{font-size:24px;margin-top:28px}.doc h2{font-size:20px}.doc h3{font-size:17px}
.toc{columns:2 260px;font-size:15px}.toc a{display:block;padding:3px 0;text-decoration:none}.toc a.l2{padding-left:14px;font-size:14px;color:var(--mut)}
.stat{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:10px}.stat div{background:var(--soft);border-radius:12px;padding:12px}.stat b{display:block;font-size:24px}
table.t{border-collapse:collapse;width:100%;font-size:15px}table.t td,table.t th{border-bottom:1px solid var(--line);padding:8px 6px;text-align:left}
.marks{display:flex;gap:6px;flex-wrap:wrap}.marks button{min-width:46px}
.hide{display:none!important}
.kbd{font-size:13px;color:var(--mut)}
.notice{background:#fff4d6;color:#5c3d00;border-radius:12px;padding:10px 14px;font-size:14px}[data-theme=dark] .notice{background:#3a2e10;color:#fde68a}