:root{--bg:#091225;--panel:#111f39;--panel2:#172946;--text:#f6f8fc;--muted:#aebed6;--cyan:#55d4ef;--green:#61d998;--pink:#ef5da8;--orange:#ffab54;--line:#263b5c;--shadow:0 20px 60px rgba(0,0,0,.25)}*{box-sizing:border-box}html{color-scheme:dark}body{margin:0;background:radial-gradient(circle at 10% 0%,#142b4d 0,transparent 36%),linear-gradient(180deg,#081123,#0a1427 60%,#08101e);color:var(--text);font:16px/1.55 Inter,ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif;min-height:100vh}a{color:inherit;text-decoration:none}.container{max-width:1180px;margin:0 auto;padding:34px 24px 70px}.topbar{height:76px;border-bottom:1px solid rgba(255,255,255,.08);background:rgba(8,17,35,.9);backdrop-filter:blur(16px);display:flex;align-items:center;justify-content:space-between;padding:0 max(24px,calc((100vw - 1180px)/2));position:sticky;top:0;z-index:10}.brand{display:flex;align-items:center;gap:12px}.brand-mark,.login-logo span{display:grid;place-items:center;background:linear-gradient(135deg,var(--cyan),#7b8cff);color:#061223;font-weight:900}.brand-mark{width:42px;height:42px;border-radius:13px}.brand small{display:block;color:var(--muted);font-size:11px;letter-spacing:.08em}.topbar nav{display:flex;gap:18px;align-items:center}.topbar nav a{color:var(--muted);font-weight:700}.topbar nav .logout{color:#fff;padding:9px 14px;border:1px solid var(--line);border-radius:10px}.hero{padding:20px 0 30px}.hero.compact h1{font-size:clamp(34px,5vw,58px);line-height:1.05;margin:8px 0 10px}.hero p{color:var(--muted);max-width:760px}.eyebrow{margin:0;color:var(--cyan)!important;font-size:12px!important;font-weight:900;letter-spacing:.14em}.subject-grid,.grade-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.subject-card,.grade-card{background:linear-gradient(150deg,rgba(24,44,77,.95),rgba(13,28,52,.95));border:1px solid var(--line);border-radius:24px;padding:28px;display:flex;gap:24px;min-height:210px;box-shadow:var(--shadow);transition:.2s transform,.2s border}.subject-card:not(.disabled):hover,.grade-card:hover,.lesson-card:hover{transform:translateY(-3px);border-color:#4a739f}.subject-card.disabled{opacity:.5}.subject-icon{font-size:54px}.subject-card h2,.grade-card h2{font-size:30px;margin:7px 0}.subject-card p,.grade-card p,.lesson-card p,.info-card p{color:var(--muted);margin:5px 0 14px}.pill,.status{display:inline-block;padding:5px 9px;border-radius:999px;background:#263854;color:#c4d3e8;font-size:11px;font-weight:900;text-transform:uppercase;letter-spacing:.06em}.pill.active,.status.ready{background:rgba(97,217,152,.15);color:var(--green)}.status.upload{background:rgba(255,171,84,.13);color:var(--orange)}.grade-no{font-size:76px;line-height:1;font-weight:900;color:rgba(85,212,239,.18);min-width:98px}.breadcrumb{display:flex;gap:9px;align-items:center;color:var(--muted);font-size:13px;flex-wrap:wrap}.breadcrumb a:hover{color:var(--cyan)}.topic-block{margin:18px 0 42px}.topic-head{display:flex;justify-content:space-between;align-items:end;margin-bottom:16px}.topic-head h2{margin:4px 0;font-size:28px}.topic-head>span{color:var(--muted);font-weight:700}.lesson-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.lesson-card{display:grid;grid-template-columns:62px 1fr auto;align-items:center;gap:16px;background:rgba(17,31,57,.85);border:1px solid var(--line);border-radius:16px;padding:17px 18px;transition:.18s}.lesson-code{display:grid;place-items:center;height:46px;background:#1d385d;border-radius:12px;color:var(--cyan);font-weight:900}.lesson-card h3{font-size:17px;margin:0}.lesson-card p{font-size:12px;margin:3px 0}.login-wrap{min-height:calc(100vh - 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