/* Рабочая тетрадь — оформление по брендбуку v1.0: тёмная тема основная, светлая дополнительная.
   Шрифты: Onest (текст и интерфейс), JetBrains Mono (знак, пути, цифры, ответы), Source Serif 4 (титул). */
@font-face{font-family:"Onest";src:url(/static/fonts/Onest.woff) format("woff");font-weight:100 900;font-display:swap}
@font-face{font-family:"JetBrains Mono";src:url(/static/fonts/JetBrainsMono.woff) format("woff");font-weight:100 800;font-display:swap}
@font-face{font-family:"Source Serif 4";src:url(/static/fonts/SourceSerif4.woff) format("woff");font-weight:500;font-display:swap}

[hidden]{display:none!important}
img{max-width:100%}
html{-webkit-text-size-adjust:100%}

:root,:root[data-theme="dark"]{
  --paper:#070B09; --surface:#0D1410; --sheet:#0D1410; --raise:#111A15;
  --ink:#E6ECE8; --muted:#8C9A92; --faint:#5C6B63; --line:#1C2721; --line2:#2A3A31;
  --grid:rgba(190,230,205,.05);
  --blue:#6EE7B7; --blue-soft:#12201A; --primary-bg:#6EE7B7; --primary-fg:#04140C; --logo:#6EE7B7; --colon:#6EE7B7;
  --ok:#A3E635; --ok-fill:#A3E635; --on-ok:#0D1A04; --ok-soft:rgba(163,230,53,.12);
  --warn:#FBBF24; --warn-fill:#FBBF24; --warn-soft:rgba(251,191,36,.12);
  --pen:#F87171; --pen-soft:rgba(248,113,113,.13);
  --chip:#141D18; --shadow:0 1px 0 rgba(0,0,0,.4); --pop:0 18px 40px -12px rgba(0,0,0,.7);
  color-scheme:dark;
}
:root[data-theme="light"]{
  --paper:#F3F4F1; --surface:#FFFFFF; --sheet:#FFFFFF; --raise:#F8F9F7;
  --ink:#0B110D; --muted:#5A645D; --faint:#8A938C; --line:#E2E5E0; --line2:#CDD2CB;
  --grid:rgba(11,17,13,.045);
  --blue:#0E7A4A; --blue-soft:#E3F1E9; --primary-bg:#0B110D; --primary-fg:#FFFFFF; --logo:#0B110D; --colon:#0E7A4A;
  --ok:#4D7C0F; --ok-fill:#65A30D; --on-ok:#FFFFFF; --ok-soft:#EEF6E2;
  --warn:#B45309; --warn-fill:#D97706; --warn-soft:#FDF1DF;
  --pen:#DC2626; --pen-soft:#FDECEC;
  --chip:#EEF0EC; --shadow:0 1px 2px rgba(11,17,13,.05),0 6px 18px -10px rgba(11,17,13,.18); --pop:0 24px 50px -20px rgba(11,17,13,.35);
  color-scheme:light;
}
:root{
  --f-ui:"Onest",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --f-serif:"Source Serif 4",Georgia,"Times New Roman",serif;
  --f-pen:var(--f-mono);
}

*{box-sizing:border-box}
body{background:var(--paper);color:var(--ink);font:15px/1.5 var(--f-ui);margin:0;min-height:100vh}
.gridbg{position:fixed;inset:0;z-index:0;pointer-events:none;background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);background-size:32px 32px}
button,input,select,textarea{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--blue);outline-offset:2px;border-radius:6px}
::selection{background:var(--blue);color:var(--primary-fg)}
.wrap{max-width:1240px;margin:0 auto;padding-left:max(20px,env(safe-area-inset-left,0px));padding-right:max(20px,env(safe-area-inset-right,0px));position:relative;z-index:1}

/* ---------- шапка ---------- */
body::before{content:"";position:fixed;inset:0 0 auto;height:env(safe-area-inset-top,0px);z-index:10;background:var(--paper)}
header.top{position:sticky;top:env(safe-area-inset-top,0px);z-index:5;background:color-mix(in srgb,var(--paper) 86%,transparent);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.top .wrap{display:flex;align-items:center;gap:12px 22px;flex-wrap:wrap;padding-block:12px}
.brand{display:flex;align-items:center;gap:12px;text-decoration:none;color:var(--ink)}
.logo{width:44px;height:28px;flex:none;fill:var(--logo)}
.logo .colon{fill:var(--colon)}
.bn{display:flex;flex-direction:column;line-height:1.2}
.bn b{font-weight:700;font-size:15px;letter-spacing:-.01em}
.bn span{font:500 9.5px/1.6 var(--f-mono);letter-spacing:.16em;color:var(--muted)}
.path{flex:1 1 auto;min-width:0;font:500 13.5px var(--f-mono);color:var(--muted);display:flex;align-items:center;gap:8px;white-space:nowrap;overflow:hidden}
.path b{color:var(--blue);font-weight:800}
.path i{font-style:normal;color:var(--faint)}
.path em{font-style:normal;color:var(--ink)}
.path .cur{display:inline-block;width:8px;height:16px;background:var(--blue);opacity:.85}
@media (prefers-reduced-motion:no-preference){.path .cur{animation:blink 1.1s steps(1) infinite}@keyframes blink{50%{opacity:0}}}
.who{display:flex;align-items:center;gap:10px;color:var(--muted);font-size:14px;flex-wrap:wrap}
.who select{border:1px solid var(--line2);background:var(--surface);border-radius:8px;padding:5px 8px}
.who .me{font-weight:600;color:var(--ink)}
.who .stu{display:flex;align-items:center;gap:8px;padding:4px 4px 4px 12px;border:1px solid var(--line2);border-radius:10px;font:500 12px var(--f-mono);letter-spacing:.04em;color:var(--muted)}
.who .stu select{font:600 14px var(--f-ui);border-color:transparent;background:transparent}
.theme{display:flex;gap:2px;padding:3px;border:1px solid var(--line2);border-radius:11px;background:var(--surface)}
.theme button{display:flex;align-items:center;gap:6px;border:0;background:transparent;color:var(--muted);padding:6px 10px;border-radius:8px;cursor:pointer;font:500 12.5px var(--f-mono);min-height:32px}
.theme svg{width:15px;height:15px;fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:round}
.theme button[data-theme-set="dark"] svg{fill:currentColor;stroke:none}
.theme button[aria-pressed="true"]{background:var(--blue-soft);color:var(--blue)}
:root[data-theme="light"] .theme button[aria-pressed="true"]{background:var(--primary-bg);color:var(--primary-fg)}
@media (max-width:980px){.path{display:none}.brand{margin-right:auto}}
@media (max-width:560px){.bn span{display:none}.theme span{display:none}.theme button{padding:6px 8px}.who{width:100%;order:5}}

/* ---------- каркас ---------- */
.shell{display:grid;grid-template-columns:220px minmax(0,1fr);gap:32px;padding-block:28px 72px}
nav.rail{display:flex;flex-direction:column;gap:2px;position:sticky;top:88px;align-self:start}
nav.rail button{all:unset;display:flex;align-items:center;gap:12px;cursor:pointer;min-height:44px;padding:0 12px;border-radius:10px;color:var(--muted);font:500 14px var(--f-mono)}
nav.rail button svg{width:18px;height:18px;flex:none;fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}
nav.rail button:hover{color:var(--ink);background:var(--chip)}
nav.rail button[aria-current="true"]{background:var(--blue-soft);color:var(--blue);font-weight:600}
:root[data-theme="light"] nav.rail button[aria-current="true"]{background:var(--primary-bg);color:var(--primary-fg)}
:root[data-theme="light"] nav.rail button[aria-current="true"] svg{stroke:#6EE7B7}
nav.rail button .pill,nav.rail button .badge{margin-left:auto}
nav.rail button:focus-visible{outline:2px solid var(--blue)}
nav.rail .note{margin-top:18px;font-size:12.5px;color:var(--muted);line-height:1.45;padding:0 12px}
@media (max-width:860px){
  .shell{grid-template-columns:minmax(0,1fr);gap:16px;padding-block:14px 48px}
  nav.rail{position:static;flex-direction:row;overflow-x:auto;gap:4px;padding-bottom:2px}
  nav.rail button{white-space:nowrap;border:1px solid var(--line2);min-height:40px}
  nav.rail .note{display:none}
}
main{min-width:0}
h1{font:700 28px/1.2 var(--f-mono);margin:0 0 6px;letter-spacing:-.02em;text-wrap:balance}
h2{font-size:17px;font-weight:600;margin:0;letter-spacing:-.01em;text-wrap:balance}
h3{font-weight:600}
.sub{color:var(--muted);margin:0 0 22px;max-width:72ch}
.stack{display:flex;flex-direction:column;gap:16px}
.row{display:flex;gap:12px;flex-wrap:wrap;align-items:center}
.grow{flex:1 1 auto;min-width:0}
.muted{color:var(--muted)}
.small{font-size:13px}
.panel{background:var(--surface);border:1px solid var(--line);border-radius:18px;padding:22px;box-shadow:var(--shadow)}
.panel > h2{margin-bottom:14px}

/* кнопки и поля */
.btn{border:1px solid var(--line2);background:var(--surface);padding:8px 15px;border-radius:10px;cursor:pointer;font-weight:600;font-size:14px;min-height:38px;transition:border-color .15s,background .15s}
.btn:hover{border-color:var(--blue)}
a.btn{text-decoration:none;color:var(--ink);display:inline-flex;align-items:center}
.msg a{color:var(--blue)}
.btn.primary{background:var(--primary-bg);border-color:var(--primary-bg);color:var(--primary-fg)}
.btn.primary:hover{filter:brightness(1.07)}
:root[data-theme="light"] .btn.primary:hover{filter:none;background:#1F2A23}
.btn.ghost{border-color:transparent;background:transparent;color:var(--blue);padding-inline:8px}
.btn:disabled{opacity:.5;cursor:default}
input[type=text],input[type=password],input[type=date],input[type=time],input[type=search],input[type=number],select,textarea{border:1px solid var(--line2);background:var(--raise);border-radius:10px;padding:8px 12px;min-width:0;min-height:38px}
input:focus,select:focus,textarea:focus{border-color:var(--blue);outline:none;box-shadow:0 0 0 3px color-mix(in srgb,var(--blue) 22%,transparent)}
textarea{width:100%;resize:vertical}
label.f{display:flex;flex-direction:column;gap:6px;font:500 11px var(--f-mono);letter-spacing:.1em;text-transform:uppercase;color:var(--muted)}
label.f > *{color:var(--ink);font:15px var(--f-ui);letter-spacing:0;text-transform:none}

/* плашки */
.pill{display:inline-flex;align-items:center;gap:6px;font:500 12px var(--f-mono);padding:3px 9px;border-radius:999px;background:var(--chip);color:var(--muted);white-space:nowrap}
.pill.ok{background:var(--ok-soft);color:var(--ok)}
.pill.bad{background:var(--pen-soft);color:var(--pen)}
.pill.warn{background:var(--warn-soft);color:var(--warn)}
.pill.blue{background:var(--blue-soft);color:var(--blue)}
.chips{display:flex;flex-wrap:wrap;gap:6px}
.chip{border:1px solid var(--line2);background:var(--surface);border-radius:999px;padding:5px 13px;cursor:pointer;font-size:13.5px}
.chip[aria-pressed="true"]{background:var(--blue);border-color:var(--blue);color:var(--primary-fg)}
:root[data-theme="light"] .chip[aria-pressed="true"]{background:var(--primary-bg);border-color:var(--primary-bg)}

/* лист задачи: условие — как на экзамене, без выделений */
.sheet{position:relative;background:var(--sheet);border:1px solid var(--line);border-radius:18px;padding:26px 28px;box-shadow:var(--shadow)}
.task-text{font-size:16.5px;line-height:1.7}
.task-text p{margin:0 0 10px;max-width:72ch}
.task-text ul.cmds{list-style:none;margin:0 0 10px;padding:0}
.task-text ul.cmds li{padding:1px 0}
.tbl-wrap{overflow-x:auto;margin:0 0 12px}
.tbl-wrap table{border-collapse:collapse;font:13px var(--f-mono);font-variant-numeric:tabular-nums;background:var(--raise)}
.tbl-wrap td{border:1px solid var(--line2);padding:4px 8px;text-align:center}
.tbl-wrap tr:first-child td{color:var(--muted)}
.tno{font:500 12px var(--f-mono);letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}
pre.code{margin:0;background:var(--raise);border:1px solid var(--line);border-radius:10px;padding:12px 14px;overflow-x:auto;font:13px/1.6 var(--f-mono);tab-size:4}
.mark{display:inline-flex;align-items:center;gap:6px;font:700 14px var(--f-mono);color:var(--pen);background:var(--pen-soft);padding:4px 10px;border-radius:8px}
.mark::before{content:"✗"}
.mark.okm{color:var(--ok);background:var(--ok-soft)}
.mark.okm::before{content:"✓"}
.answer-row{display:flex;gap:10px;flex-wrap:wrap;align-items:center;margin-top:18px}
.answer-row input{font:500 17px var(--f-mono);width:220px;min-height:48px;padding-inline:16px}
.answer-row .btn.primary{min-height:48px;padding-inline:22px}

/* списки */
.list{display:flex;flex-direction:column}
.item{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:12px;align-items:center;padding:13px 6px;border-top:1px solid var(--line)}
.item:first-child{border-top:0}
.item .t{min-width:0}
.item .t b{font-weight:600}
.clickable{cursor:pointer;border-radius:10px}
.clickable:hover{background:var(--chip)}
.dots{display:flex;gap:4px;flex-wrap:wrap}
.dot{width:24px;height:24px;border-radius:7px;display:grid;place-items:center;font:600 11px var(--f-mono);background:var(--chip);color:var(--muted)}
.dot.ok{background:var(--ok-fill);color:var(--on-ok)}
.dot.bad{background:var(--pen);color:var(--surface)}
.dot.try{background:var(--warn-soft);color:var(--warn)}

/* прогресс */
.egegrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(54px,1fr));gap:6px}
.ege{border:1px solid var(--line2);border-radius:10px;padding:7px 4px;text-align:center;background:var(--surface)}
.ege b{display:block;font:600 16px var(--f-mono)}
.ege span{font-size:10.5px;color:var(--muted)}
.ege.done{background:var(--ok-soft);border-color:transparent}.ege.done b{color:var(--ok)}
.ege.prog{background:var(--warn-soft);border-color:transparent}.ege.prog b{color:var(--warn)}
.ege.none{opacity:.6}
.bar{height:6px;border-radius:99px;background:var(--chip);overflow:hidden;display:flex;gap:2px}
.bar i{display:block;height:100%;border-radius:99px}
.bar i.a{background:var(--ok-fill)}.bar i.b{background:var(--warn-fill)}
.sgrid{display:grid;grid-template-columns:minmax(0,1.6fr) 80px 90px minmax(80px,1fr);gap:8px 14px;align-items:center;font-size:14px}
.sgrid .h,.tgrid .h{font:500 11px var(--f-mono);color:var(--muted);text-transform:uppercase;letter-spacing:.1em}
.num{font-family:var(--f-mono);font-variant-numeric:tabular-nums}
@media (max-width:620px){.sgrid{grid-template-columns:minmax(0,1fr) 64px 70px}.sgrid .hb{display:none}}
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:12px}
.stat{border:1px solid var(--line);border-radius:14px;padding:14px 16px;background:var(--surface);box-shadow:var(--shadow)}
.stat .v{font:700 26px/1.1 var(--f-mono);font-variant-numeric:tabular-nums}
.stat .k{font-size:12.5px;color:var(--muted);margin-top:2px}
.streak .v{color:var(--warn)}

/* таблицы */
.tablewrap{overflow-x:auto}
table.j{border-collapse:collapse;width:100%;font-size:14px}
table.j th{font:500 11px var(--f-mono);color:var(--muted);text-align:left;text-transform:uppercase;letter-spacing:.1em;padding:8px;border-bottom:1px solid var(--line2)}
table.j td{padding:9px 8px;border-bottom:1px solid var(--line);white-space:nowrap}

/* разное */
.push{display:flex;gap:12px;align-items:flex-start;background:var(--surface);border:1px solid var(--line);border-radius:16px;padding:12px 14px;box-shadow:var(--pop);max-width:520px}
.push .ic{width:34px;height:34px;border-radius:9px;background:#0B110D;color:#6EE7B7;display:grid;place-items:center;font:800 12px var(--f-mono);flex:none}
.push .tt{font-weight:600}
.toast{position:fixed;left:50%;bottom:calc(20px + env(safe-area-inset-bottom,0px));transform:translateX(-50%);background:var(--ink);color:var(--paper);padding:11px 18px;border-radius:12px;font-weight:600;z-index:20;box-shadow:var(--pop)}
details.sol{margin-top:16px;border-top:1px dashed var(--line2);padding-top:12px}
details.sol summary{cursor:pointer;color:var(--blue);font-weight:600}
.sol .idea{max-width:72ch;margin:8px 0 10px}
.empty{padding:32px;text-align:center;color:var(--muted);border:1px dashed var(--line2);border-radius:16px;background:color-mix(in srgb,var(--surface) 60%,transparent)}
.two{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:16px}
@media (max-width:900px){.two{grid-template-columns:minmax(0,1fr)}}
.loading{padding:60px 0;text-align:center;color:var(--muted);font-family:var(--f-mono)}
.next{display:flex;gap:16px;align-items:center;flex-wrap:wrap;background:var(--surface);border:1px solid var(--line);border-radius:16px;padding:14px 16px;box-shadow:var(--shadow)}
.cal{width:56px;flex:none;border-radius:11px;overflow:hidden;border:1px solid var(--line2);text-align:center;background:var(--raise)}
.cal i{display:block;font:600 10.5px var(--f-mono);font-style:normal;background:var(--primary-bg);color:var(--primary-fg);padding:3px 0;text-transform:uppercase;letter-spacing:.1em}
.cal b{display:block;font:700 22px/1.3 var(--f-mono);padding:2px 0 3px}
.msgs{display:flex;flex-direction:column;gap:10px}
.msg{border:1px solid var(--line);border-left:3px solid var(--blue);border-radius:12px;padding:10px 12px;background:var(--surface)}
.msg p{margin:0;white-space:pre-wrap;overflow-wrap:anywhere;max-width:72ch}
.msg img{display:block;max-height:340px;border-radius:8px;margin-top:6px}
.msg pre.code{margin-top:6px;max-height:320px}
.msg .meta{font:12px var(--f-mono);color:var(--muted);margin-bottom:4px}
.file{display:inline-flex;align-items:center;gap:8px;margin-top:6px;padding:7px 11px;border:1px solid var(--line2);border-radius:10px;background:var(--raise);font-size:14px}
.compose{display:flex;flex-direction:column;gap:8px}
.compose textarea{min-height:64px}
.ic-ok{display:inline-block;width:11px;height:11px;flex:none;vertical-align:-1px}
.chat{display:flex;flex-direction:column;gap:8px;max-height:460px;overflow-y:auto;padding:8px 2px 12px;margin:10px 0 12px;border-block:1px solid var(--line)}
.bub{max-width:min(80%,560px);align-self:flex-start;background:var(--chip);border-radius:14px 14px 14px 4px;padding:9px 13px;min-width:0}
.bub.me{align-self:flex-end;background:var(--blue-soft);border-radius:14px 14px 4px 14px}
.bub .meta{font:11.5px var(--f-mono);color:var(--muted);margin-bottom:3px;display:flex;gap:8px;align-items:center;flex-wrap:wrap}
.bub p{margin:0;white-space:pre-wrap;overflow-wrap:anywhere}
.bub a{color:var(--blue)}
.bub img{display:block;max-width:100%;max-height:320px;border-radius:8px;margin-top:6px}
.bub pre.code{margin-top:6px;max-height:300px;background:var(--surface)}
.bub .file{background:var(--surface)}
.dayline{align-self:center;font:11.5px var(--f-mono);letter-spacing:.06em;color:var(--muted);padding:4px 0}
.topic{border-top:1px solid var(--line);padding-top:16px;margin-top:16px}
.topic:first-child{border-top:0;padding-top:0;margin-top:0}
.topic-h{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin-bottom:8px}
.topic-h h3{margin:0;font-size:15.5px;flex:1 1 auto;min-width:0}
.topic-h .bar{width:120px}
.tgrid{display:grid;grid-template-columns:minmax(0,1.7fr) 110px 100px auto;gap:8px 14px;align-items:center;font-size:14px}
.tid{font:600 12.5px var(--f-mono);background:var(--chip);border-radius:6px;padding:2px 7px;margin-right:6px;white-space:nowrap}
@media (max-width:640px){.tgrid{grid-template-columns:minmax(0,1fr) 84px}.tgrid .h{display:none}.tgrid div.hb{grid-column:1/-1;justify-content:flex-start!important;padding-bottom:6px;border-bottom:1px dashed var(--line)}}
.tiles{display:flex;flex-wrap:wrap;gap:6px}
.tiles .ege{min-width:56px}
.imp-cols{border-collapse:collapse;font-size:13.5px;width:100%}
.imp-cols th,.imp-cols td{border:1px solid var(--line2);padding:7px 9px;text-align:left;vertical-align:top}
.imp-cols th{background:var(--chip);font-weight:600}
.imp-cols td.ex{font:12.5px/1.45 var(--f-mono);white-space:pre-wrap;color:var(--muted)}
.imp-rows td{white-space:normal}
.task-img{display:block;max-width:100%;max-height:440px;margin:6px 0 12px;border-radius:8px;background:#fff;border:1px solid var(--line2)}
.imgchips{display:flex;flex-wrap:wrap;gap:10px}
.imgchip{display:flex;flex-direction:column;gap:4px;align-items:flex-start;border:1px solid var(--line2);border-radius:10px;padding:6px;background:var(--surface);max-width:180px}
.imgchip img{max-width:166px;max-height:110px;border-radius:4px;background:#fff}
.imgchip span{font:12px var(--f-mono);overflow-wrap:anywhere}
.warnbar{background:var(--warn-soft);color:var(--warn);border-radius:12px;padding:10px 14px;font-size:14px}
.err{color:var(--pen);font-size:14px;min-height:20px}
.demo-acc{display:grid;grid-template-columns:auto minmax(0,1fr) auto;gap:6px 12px;align-items:center;font-size:13.5px}
.demo-acc button{justify-self:start}
.cred{font:13px var(--f-mono);background:var(--chip);padding:1px 6px;border-radius:5px}
.live{display:inline-flex;align-items:center;gap:8px;color:var(--blue);font:600 13px var(--f-mono)}
.live::before{content:"";width:8px;height:8px;border-radius:50%;background:var(--blue)}
@media (prefers-reduced-motion:no-preference){.live::before{animation:pulse 1.6s ease-in-out infinite}@keyframes pulse{50%{opacity:.3}}}
.badge{display:inline-block;width:8px;height:8px;border-radius:50%;background:var(--blue);margin-left:7px;vertical-align:middle}
.feed{display:flex;flex-direction:column;gap:10px}
.fitem{border:1px solid var(--line);border-radius:12px;padding:11px 13px;background:var(--surface)}
.fitem.new{border-color:var(--blue)}
.tries{display:flex;gap:5px;flex-wrap:wrap;margin-top:6px}
.ege.btnlike{cursor:pointer;font:inherit;color:inherit}
.ege.btnlike:hover{border-color:var(--blue)}
.lessontask + .lessontask{margin-top:16px}
.passbtn{font-size:12.5px;padding:2px 10px;margin-left:8px;min-height:30px}
@media (prefers-reduced-motion:no-preference){.fade{animation:fd .18s ease-out}@keyframes fd{from{opacity:.4;transform:translateY(3px)}to{opacity:1;transform:none}}}

/* ---------- стартовая страница и вход ---------- */
.shell.noauth{grid-template-columns:minmax(0,1fr);padding-block:12px 64px}
.start{position:relative;display:flex;align-items:center;min-height:min(640px,calc(100vh - 120px))}
.start-text{position:relative;z-index:2;max-width:470px;padding:32px 0}
.title{font:500 clamp(54px,8vw,92px)/.98 var(--f-serif);letter-spacing:-.03em;margin:0}
.kicker{margin-top:20px;font:500 15px var(--f-mono);letter-spacing:.28em;color:var(--muted)}
.lead-mono{margin:18px 0 0;font:15px/1.65 var(--f-mono);color:var(--muted);max-width:420px}
.login-card{margin-top:28px;background:color-mix(in srgb,var(--surface) 88%,transparent);backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px);border:1px solid var(--line2);border-radius:18px;padding:22px;display:flex;flex-direction:column;gap:12px;box-shadow:var(--pop)}
.login-card input{width:100%;min-height:46px}
.login-card .btn.primary{min-height:48px;font-size:15px;display:flex;align-items:center;justify-content:center;gap:10px}
.login-card .btn.primary svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
:root[data-theme="light"] .login-card .btn.primary svg{stroke:#6EE7B7}
.start-note{font-size:13px;color:var(--muted);margin:14px 4px 0;max-width:420px}
.start-art{position:absolute;z-index:1;top:0;bottom:0;right:-20px;width:62%;overflow:hidden;pointer-events:none}
.start-art img{display:block;width:100%;height:100%;object-fit:cover;object-position:50% 55%}
.start-art::after{content:"";position:absolute;inset:0;background:linear-gradient(var(--grid) 1px,transparent 1px) fixed,linear-gradient(90deg,var(--grid) 1px,transparent 1px) fixed,linear-gradient(90deg,var(--paper) 0%,color-mix(in srgb,var(--paper) 55%,transparent) 22%,transparent 50%),linear-gradient(0deg,var(--paper) 0%,transparent 20%),linear-gradient(180deg,var(--paper) 0%,transparent 14%),linear-gradient(270deg,var(--paper) 0%,transparent 12%);background-size:32px 32px,32px 32px,auto,auto,auto,auto}
.art-cap{position:absolute;z-index:3;top:18px;right:6px;font:500 11.5px/2 var(--f-mono);letter-spacing:.14em;color:var(--muted);text-align:left}
:root[data-theme="light"] .start{gap:36px}
:root[data-theme="light"] .start-art{position:relative;right:auto;flex:1 1 0;width:auto;height:min(540px,70vh);border-radius:28px;background:#050806;box-shadow:var(--pop)}
:root[data-theme="light"] .start-art::after{display:none}
:root[data-theme="light"] .art-cap{top:22px;right:26px;color:rgba(232,238,234,.62)}
:root[data-theme="light"] .start-text{flex:0 1 470px}
.features{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:28px}
.feat{background:color-mix(in srgb,var(--surface) 80%,transparent);border:1px solid var(--line);border-radius:16px;padding:22px 24px;box-shadow:var(--shadow)}
.feat .no{font:600 13px var(--f-mono);color:var(--blue)}
.feat h2{margin-top:12px}
.feat p{margin:8px 0 0;font:12.5px/1.7 var(--f-mono);color:var(--muted)}
@media (max-width:860px){
  .start{flex-direction:column;align-items:stretch;min-height:0}
  .start-art,:root[data-theme="light"] .start-art{position:relative;order:-1;right:auto;width:auto;height:230px;flex:none;border-radius:22px;background:#050806;margin-top:8px}
  .start-art::after{background:linear-gradient(0deg,rgba(5,8,6,.55) 0%,transparent 40%)}
  .art-cap{display:none}
  .start-text{padding-top:20px}
  .features{grid-template-columns:minmax(0,1fr)}
}

/* ---------- видеозвонок ---------- */
.call{position:fixed;z-index:30;background:#050806;color:#E6ECE8;border:1px solid #24342B;box-shadow:0 24px 60px -18px rgba(0,0,0,.75);display:flex;flex-direction:column;overflow:hidden}
.call.dock{right:max(16px,env(safe-area-inset-right,0px));bottom:calc(16px + env(safe-area-inset-bottom,0px));width:min(400px,calc(100vw - 32px));border-radius:18px}
.call.dock .call-stage{aspect-ratio:16/10;flex:1 1 auto}
.call.dock[style*="height"] .call-stage{aspect-ratio:auto}
.call.max{inset:calc(12px + env(safe-area-inset-top,0px)) 12px calc(12px + env(safe-area-inset-bottom,0px));border-radius:22px}
.call.max .call-stage{flex:1 1 auto}
.call:fullscreen{inset:0;border-radius:0;border:0}
.call-stage{position:relative;min-height:0;background:#030504}
#call-rv{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;background:#030504}
.call.rshare #call-rv,.call.max #call-rv{object-fit:contain}
.call-ph{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px;font:500 13px var(--f-mono);color:#8C9A92;text-align:center;padding:12px}
.call-av{width:64px;height:64px;border-radius:50%;display:grid;place-items:center;background:#12201A;color:#6EE7B7;font:700 26px var(--f-mono);flex:none}
.call-av.sm{width:42px;height:42px;font-size:16px}
.call-av svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}
.call.dock .call-av{width:52px;height:52px;font-size:21px}
.call-self{position:absolute;right:10px;bottom:10px;width:28%;max-width:200px;aspect-ratio:4/3;object-fit:cover;border-radius:12px;border:1px solid rgba(255,255,255,.18);background:#0D1410;transform:scaleX(-1);box-shadow:0 8px 20px rgba(0,0,0,.5)}
.call-self.scr{transform:none;object-fit:contain;aspect-ratio:16/10}
.call-top{position:absolute;left:0;right:0;top:0;display:flex;align-items:center;gap:10px;padding:10px 14px;background:linear-gradient(180deg,rgba(3,5,4,.75),transparent);font-size:14px}
.call-name{font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.call-meta{margin-left:auto;display:flex;align-items:center;gap:10px;font:500 12.5px var(--f-mono);color:#B4C0B9;white-space:nowrap}
.q{display:inline-flex;align-items:flex-end;gap:2px;height:12px}
.q i{width:3px;border-radius:1px;background:#4E5C54}
.q i:nth-child(1){height:5px}.q i:nth-child(2){height:8px}.q i:nth-child(3){height:12px}
.q.good i{background:#A3E635}.q.ok i:nth-child(-n+2){background:#FBBF24}.q.poor i:nth-child(1){background:#F87171}
.relay{font-size:11px;padding:1px 7px;border-radius:99px;background:rgba(251,191,36,.15);color:#FBBF24}
.call-flags{position:absolute;left:12px;bottom:12px;display:flex;flex-direction:column;align-items:flex-start;gap:6px;max-width:60%}
.call-flags span{display:inline-flex;align-items:center;gap:6px;font-size:12.5px;background:rgba(3,5,4,.72);padding:4px 10px;border-radius:99px}
.call-flags svg{width:14px;height:14px;fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:round}
.call-bar{display:flex;align-items:center;gap:6px;padding:10px 12px;background:#0B110D;border-top:1px solid #1C2721;flex-wrap:wrap}
.cb-sp{flex:1 1 auto}
.cb{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-width:44px;height:44px;padding:0 12px;border-radius:12px;border:1px solid #24342B;background:#111A15;color:#E6ECE8;cursor:pointer;font:600 13.5px var(--f-ui)}
.cb svg{width:19px;height:19px;flex:none;fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}
.cb:hover{border-color:#6EE7B7}
.cb.off{background:#3A1B1B;border-color:#5A2626;color:#FCA5A5}
.cb.on{background:#6EE7B7;border-color:#6EE7B7;color:#04140C}
.cb.hang{background:#DC2626;border-color:#DC2626;color:#fff}
.cb.hang:hover{background:#EF4444}
.cb.ok{background:#16A34A;border-color:#16A34A;color:#fff}
.cb:focus-visible{outline:2px solid #6EE7B7;outline-offset:2px}
.call.dock .cb{min-width:40px;height:40px;padding:0 9px}
.call.dock .cb.wide span,.call.dock #cb-full{display:none}
.call-set{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:10px;padding:12px 14px;background:#0B110D;border-top:1px solid #1C2721}
.call-set label.f{color:#8C9A92}
.call-set select{background:#111A15;border-color:#24342B;color:#E6ECE8;width:100%}
@media (max-width:560px){
  .call.dock{left:12px;right:12px;width:auto}
  .call.max .cb.wide span{display:none}
  #cb-pip{display:none}
}
.ring{position:fixed;z-index:31;top:calc(14px + env(safe-area-inset-top,0px));left:50%;transform:translateX(-50%);width:min(440px,calc(100vw - 24px));display:flex;align-items:center;gap:14px;padding:14px 16px;border-radius:20px;background:#0B110D;color:#E6ECE8;border:1px solid #2A3A31;box-shadow:0 24px 60px -16px rgba(0,0,0,.7)}
.ring .call-av{width:48px;height:48px;font-size:20px}
.ring-k{font:500 10.5px var(--f-mono);letter-spacing:.16em;color:#6EE7B7}
.ring-t{font-weight:600;font-size:16px;margin-top:2px}
.ring .cb{width:52px;height:52px;border-radius:50%;padding:0}
@media (prefers-reduced-motion:no-preference){.ring .call-av{animation:ringp 1.4s ease-out infinite}@keyframes ringp{0%{box-shadow:0 0 0 0 rgba(110,231,183,.45)}100%{box-shadow:0 0 0 16px rgba(110,231,183,0)}}}
.callpanel .call-av{background:var(--blue-soft);color:var(--blue)}
.callpanel h2{font-size:16px}
.online{color:var(--ok);font-weight:600}
.online::before{content:"";display:inline-block;width:7px;height:7px;border-radius:50%;background:var(--ok-fill);margin-right:6px;vertical-align:1px}
.call.max .call-self{width:16%;min-width:120px}
.me-btn{display:inline-flex;align-items:center;gap:6px;border:0;background:transparent;padding:4px 6px;border-radius:8px;cursor:pointer;font-weight:600;color:var(--ink)}
.me-btn svg{width:13px;height:13px;fill:none;stroke:var(--muted);stroke-width:1.4;stroke-linejoin:round}
.me-btn:hover{background:var(--chip)}
.namedlg{position:fixed;inset:0;z-index:40;background:rgba(3,5,4,.55);display:grid;place-items:start center;padding:12vh 16px 16px}
.namedlg .panel{width:min(440px,100%);box-shadow:var(--pop)}
.namedlg input{width:100%}

/* окно звонка: перетаскивание, размер, полоска */
.call.dock{touch-action:none}
.call.dock .call-top{cursor:grab}
.call.dock.dragging,.call.dock.dragging .call-top{cursor:grabbing;user-select:none}
.call-grab{display:none;width:14px;height:10px;flex:none;background-image:radial-gradient(circle,#8C9A92 1.2px,transparent 1.4px);background-size:5px 5px;opacity:.8}
.call.dock .call-grab{display:inline-block}
.call-resize{display:none;position:absolute;right:0;bottom:0;width:18px;height:18px;cursor:nwse-resize;z-index:3;background:linear-gradient(135deg,transparent 50%,#4E5C54 50%,#4E5C54 58%,transparent 58%,transparent 70%,#4E5C54 70%,#4E5C54 78%,transparent 78%)}
.call.dock:not(.mini) .call-resize{display:block}
.call.dock .call-bar{padding-right:22px}
.call-mini-info{display:none;font:500 12.5px var(--f-mono);color:#B4C0B9;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:160px}
.call.mini .call-stage,.call.mini #call-set{display:none!important}
.call.mini .call-mini-info{display:inline}
.call.mini{width:auto!important;height:auto!important;max-width:calc(100vw - 16px)}
.call.mini .call-bar{cursor:grab;border-top:0}
.call.mini #cb-pip,.call.mini #cb-set{display:none}
@media (max-width:560px){.call.dock{left:12px;right:12px}.call-resize{display:none!important}}

.call.max.fs{inset:0;border-radius:0;border:0;height:100vh;height:100dvh;padding:env(safe-area-inset-top,0px) env(safe-area-inset-right,0px) env(safe-area-inset-bottom,0px) env(safe-area-inset-left,0px)}
html.call-max,html.call-max body{overflow:hidden}
.linkbtn{border:0;background:none;padding:0;color:var(--blue);font:inherit;cursor:pointer;text-decoration:underline;text-underline-offset:2px}
.warn-t{color:var(--warn)}
.toast{max-width:calc(100vw - 32px);text-align:center}

/* выбор ученика */
.stu{position:relative}
.who .stu{padding:0;border:0;display:block}
.stu-btn{display:flex;align-items:center;gap:10px;min-height:44px;padding:4px 10px 4px 5px;border:1px solid var(--line2);border-radius:12px;background:var(--surface);color:var(--ink);cursor:pointer;max-width:340px;text-align:left}
.stu-btn:hover,.stu-btn[aria-expanded="true"]{border-color:var(--blue)}
.stu-av{position:relative;width:32px;height:32px;flex:none;border-radius:9px;display:grid;place-items:center;background:var(--blue-soft);color:var(--blue);font:700 14px var(--f-mono)}
.sp-on{position:absolute;right:-3px;bottom:-3px;width:10px;height:10px;border-radius:50%;background:var(--ok-fill);box-shadow:0 0 0 2px var(--surface)}
.stu-txt{display:flex;flex-direction:column;min-width:0;line-height:1.2}
.stu-k{font:500 9.5px var(--f-mono);letter-spacing:.14em;color:var(--muted)}
.stu-n{font-weight:600;font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.stu-p{font-size:12px;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.stu-live{flex:none;font:600 11px var(--f-mono);color:var(--blue);background:var(--blue-soft);padding:2px 7px;border-radius:99px}
.stu-chev{width:14px;height:14px;flex:none;fill:none;stroke:var(--muted);stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;margin-left:auto;transition:transform .15s}
.stu-btn[aria-expanded="true"] .stu-chev{transform:rotate(180deg)}
.stu-pop{position:absolute;z-index:25;top:calc(100% + 6px);left:0;min-width:300px;max-width:min(380px,calc(100vw - 24px));background:var(--surface);border:1px solid var(--line2);border-radius:14px;box-shadow:var(--pop);padding:6px}
.stu-q{width:100%;margin:2px 0 6px}
.stu-list{display:flex;flex-direction:column;gap:2px;max-height:min(360px,60vh);overflow-y:auto}
.stu-opt{display:flex;align-items:center;gap:10px;width:100%;min-height:48px;padding:6px 8px;border:0;border-radius:10px;background:transparent;color:var(--ink);cursor:pointer;text-align:left}
.stu-opt:hover,.stu-opt:focus-visible{background:var(--chip);outline:none}
.stu-opt[aria-selected="true"]{background:var(--blue-soft)}
.stu-opt .stu-txt{flex:1 1 auto}
.stu-ok{width:16px;height:16px;flex:none;fill:none;stroke:var(--blue);stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
.stu-empty{padding:14px;text-align:center;color:var(--muted);font-size:13px}
@media (max-width:560px){.stu-btn{max-width:100%}.stu-pop{left:0;right:auto}}
.who .stu{font:400 14px var(--f-ui);letter-spacing:0;color:var(--ink)}
@media (max-width:560px){.call.dock:not([style*="height"]) .call-stage{aspect-ratio:4/3}}

/* второе устройство ученика как камера */
.call-camtile{position:absolute;z-index:2;top:46px;right:10px;width:30%;max-width:220px;aspect-ratio:4/3;object-fit:cover;border-radius:12px;border:1px solid rgba(110,231,183,.55);background:#0D1410;cursor:pointer;box-shadow:0 8px 20px rgba(0,0,0,.5)}
.call-camlabel{position:absolute;z-index:3;top:50px;right:16px;max-width:calc(30% - 12px);font:500 10.5px var(--f-mono);color:#E6ECE8;background:rgba(3,5,4,.7);padding:2px 7px;border-radius:99px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;pointer-events:none}
.call.swap .call-camtile{inset:0;top:0;right:0;width:100%;height:100%;max-width:none;aspect-ratio:auto;object-fit:contain;border:0;border-radius:0;cursor:default;z-index:0;box-shadow:none}
.call.swap #call-rv{z-index:2;top:46px;right:10px;left:auto;bottom:auto;inset:auto;position:absolute;top:46px;right:10px;width:30%;max-width:220px;height:auto;aspect-ratio:4/3;object-fit:cover;border-radius:12px;border:1px solid rgba(110,231,183,.55);cursor:pointer;visibility:visible!important}
.call.max:not(.swap) .call-camtile,.call.max.swap #call-rv{max-width:300px}
.call.swap .call-camtile{background:#030504}
.camlink{position:fixed;z-index:30;left:12px;right:12px;bottom:calc(12px + env(safe-area-inset-bottom,0px));max-width:480px;margin:0 auto;background:#0B110D;color:#E6ECE8;border:1px solid #2A3A31;border-radius:20px;overflow:hidden;box-shadow:0 24px 60px -16px rgba(0,0,0,.75)}
.camlink video{display:block;width:100%;aspect-ratio:4/3;object-fit:cover;background:#030504}
.camlink video.mirror{transform:scaleX(-1)}
.camlink-b{display:flex;align-items:center;gap:12px;padding:12px 14px}
.camlink-t{font-weight:600;font-size:15px;margin-top:2px}
.camlink-s{font-size:12px;color:#8C9A92;margin-top:4px;line-height:1.4}
.call-self{z-index:3}