:root{--pri:#2563eb;--bg:#f3f4f6;--card:#fff;--tx:#111827;--mut:#6b7280;--bd:#e5e7eb;--ok:#15803d;--err:#b91c1c;--warn:#b45309}
*{box-sizing:border-box}
body{margin:0;font:15px/1.5 system-ui,-apple-system,Segoe UI,Roboto,sans-serif;background:var(--bg);color:var(--tx)}
a{color:var(--pri)}
h1,h2,h3{line-height:1.25}
.shell{display:flex;min-height:100vh}
aside{width:240px;background:#0f172a;color:#e5e7eb;display:flex;flex-direction:column;flex-shrink:0}
aside .brand{padding:18px;font-weight:700;font-size:17px;display:flex;gap:10px;align-items:center;border-bottom:1px solid #1e293b}
aside .brand img{height:32px;border-radius:6px;background:#fff}
aside nav{flex:1;padding:10px 8px;overflow:auto}
aside nav a{display:block;padding:9px 12px;border-radius:8px;color:#cbd5e1;text-decoration:none;margin-bottom:2px}
aside nav a:hover{background:#1e293b}
aside nav a.on{background:var(--pri);color:#fff}
aside .who{padding:14px 18px;border-top:1px solid #1e293b;font-size:13px}
aside .who a{color:#93c5fd}
.main{flex:1;min-width:0}
header{display:flex;align-items:center;gap:12px;padding:14px 24px;background:var(--card);border-bottom:1px solid var(--bd)}
header h1{font-size:20px;margin:0}
#burger{display:none;background:none;border:0;font-size:24px;cursor:pointer}
main{padding:24px;max-width:1200px}
main.plain{margin:0 auto;padding:24px 16px;max-width:520px}
.card{background:var(--card);border:1px solid var(--bd);border-radius:12px;padding:20px;margin-bottom:18px}
.card.narrow{max-width:460px;margin:40px auto}.center{text-align:center}
.card h2{margin-top:0;font-size:17px}
.grid{display:grid;gap:16px}
.g2{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}
.g4{grid-template-columns:repeat(auto-fit,minmax(190px,1fr))}
.kpi{background:var(--card);border:1px solid var(--bd);border-radius:12px;padding:16px}
.kpi b{display:block;font-size:26px}.kpi span{color:var(--mut);font-size:13px}
table{width:100%;border-collapse:collapse;background:var(--card)}
th,td{padding:10px 12px;border-bottom:1px solid var(--bd);text-align:left;vertical-align:top}
th{font-size:12px;text-transform:uppercase;color:var(--mut);letter-spacing:.04em}
.tw{overflow-x:auto;border:1px solid var(--bd);border-radius:12px;background:var(--card);margin-bottom:18px}
.tw table{margin:0}
label{display:block;font-weight:600;margin:12px 0 4px}
input[type=text],input[type=email],input[type=password],input[type=number],input[type=date],input[type=datetime-local],input[type=color],input[type=url],input[type=file],select,textarea{width:100%;padding:9px 11px;border:1px solid #d1d5db;border-radius:8px;font:inherit;background:#fff}
input[type=color]{padding:2px;height:40px}
textarea{min-height:110px;resize:vertical}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:14px}.row3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:14px}
.btn,button.btn{display:inline-block;background:var(--pri);color:#fff;border:0;border-radius:8px;padding:9px 16px;font:inherit;font-weight:600;cursor:pointer;text-decoration:none}
.btn.sec{background:#e5e7eb;color:#111827}.btn.red{background:var(--err)}.btn.sm{padding:5px 10px;font-size:13px}
.btn:hover{filter:brightness(.93)}
.inline{display:inline}
.actions{display:flex;gap:6px;flex-wrap:wrap;align-items:center}
.alert{padding:10px 14px;border-radius:8px;margin-bottom:14px;border:1px solid}
.alert.ok{background:#f0fdf4;border-color:#bbf7d0;color:var(--ok)}
.alert.err{background:#fef2f2;border-color:#fecaca;color:var(--err)}
.alert.warn{background:#fffbeb;border-color:#fde68a;color:var(--warn)}
.badge{display:inline-block;padding:2px 9px;border-radius:99px;font-size:12px;font-weight:600;background:#e5e7eb;color:#374151}
.badge.ok{background:#dcfce7;color:var(--ok)}.badge.err{background:#fee2e2;color:var(--err)}.badge.warn{background:#fef3c7;color:var(--warn)}.badge.blue{background:#dbeafe;color:#1d4ed8}
.bar{background:#e5e7eb;border-radius:99px;height:8px;overflow:hidden;min-width:80px}.bar i{display:block;height:100%;background:var(--pri)}
.muted{color:var(--mut)}small{color:var(--mut)}
.toolbar{display:flex;gap:10px;flex-wrap:wrap;align-items:end;margin-bottom:16px}
.toolbar>*{flex:0 0 auto}.toolbar label{margin:0 0 3px}
.toolbar select,.toolbar input{width:auto;min-width:160px}
.course{display:flex;gap:14px;align-items:center}
.course .cap{width:110px;height:70px;border-radius:8px;background:linear-gradient(135deg,var(--pri),#0f172a);object-fit:cover;flex-shrink:0}
.player{position:relative;padding-top:56.25%;background:#000;border-radius:12px;overflow:hidden}
.player iframe,.player #yt{position:absolute;inset:0;width:100%;height:100%;border:0}
.lesson-layout{display:grid;grid-template-columns:1fr 320px;gap:18px}
.toc a{display:flex;gap:8px;padding:8px 10px;border-radius:8px;text-decoration:none;color:inherit;align-items:flex-start}
.toc a:hover{background:#f3f4f6}.toc a.on{background:#eff6ff;font-weight:600}
.toc .ck{width:18px;height:18px;border-radius:50%;border:2px solid #cbd5e1;flex-shrink:0;margin-top:2px}.toc .ck.done{background:var(--ok);border-color:var(--ok)}
.toc h4{margin:14px 0 4px;font-size:13px;text-transform:uppercase;color:var(--mut)}
.q{border:1px solid var(--bd);border-radius:10px;padding:14px;margin-bottom:14px}
.q label{font-weight:400;display:flex;gap:8px;margin:6px 0;align-items:flex-start;cursor:pointer}.q label input{margin-top:5px}
.copy{font-family:monospace;font-size:12px;word-break:break-all;background:#f3f4f6;padding:6px 8px;border-radius:6px}
@media(max-width:900px){
 aside{position:fixed;inset:0 auto 0 0;transform:translateX(-100%);transition:.2s;z-index:50}
 aside.open{transform:none}
 #burger{display:block}
 main{padding:16px}header{padding:12px 16px}
 .lesson-layout,.row2,.row3{grid-template-columns:1fr}
}