:root{--bg: #f6f6f3;--surface: #fff;--text: #1d1d1b;--muted: #6b6b66;--line: #deded8;--accent: #2d5bd7;--accent-text: #fff;--ok-bg: #e5f4e8;--ok: #1e6b34;--bad-bg: #fbe7e5;--bad: #a3271b;color-scheme:light}@media(prefers-color-scheme:dark){:root{--bg: #151514;--surface: #1f1f1d;--text: #ecece8;--muted: #a0a09a;--line: #34342f;--accent: #7c9cf5;--accent-text: #10172b;--ok-bg: #173323;--ok: #8fd6a4;--bad-bg: #3a1a17;--bad: #f2a69c;color-scheme:dark}}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.5 system-ui,sans-serif}h1{font-size:1.6rem;margin:0}h2{font-size:1.15rem;margin:0}.page{max-width:760px;margin:0 auto;padding:24px 16px 64px}.narrow{max-width:420px}.top{display:flex;flex-wrap:wrap;gap:8px 16px;align-items:center;justify-content:space-between;padding:12px 16px;border-bottom:1px solid var(--line);background:var(--surface)}.top nav{display:flex;flex-wrap:wrap;gap:4px 12px;align-items:center}.stack{display:flex;flex-direction:column;gap:12px}.row{display:flex;gap:8px;align-items:center;flex-wrap:wrap}.spread{display:flex;gap:12px;align-items:center;justify-content:space-between;flex-wrap:wrap}.card{background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:16px}.muted{color:var(--muted)}.small{font-size:.875rem}label{display:flex;flex-direction:column;gap:4px}label.row{flex-direction:row}input,select{font:inherit;color:inherit;background:var(--bg);border:1px solid var(--line);border-radius:6px;padding:8px 10px}input[type=number]{width:6em}.check{flex-direction:row;align-items:flex-start;gap:10px;cursor:pointer}.check>span:first-of-type{flex:1}.check input{margin-top:4px}.lessons{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:6px;max-height:50vh;overflow:auto}.btn{font:inherit;border:1px solid var(--line);background:var(--surface);color:var(--text);border-radius:6px;padding:8px 14px;cursor:pointer}.btn.small{padding:4px 10px;font-size:.875rem}.btn.primary{background:var(--accent);border-color:var(--accent);color:var(--accent-text)}.btn:disabled{opacity:.5;cursor:not-allowed}.link{font:inherit;background:none;border:0;color:var(--accent);cursor:pointer;padding:4px 0}.link.active{color:var(--text);font-weight:600}.invite{width:min(320px,100%);font-size:.8rem}.question{font-size:1.2rem;font-weight:600}.option{font:inherit;text-align:left;padding:12px 14px;border:1px solid var(--line);border-radius:8px;background:var(--bg);color:var(--text);cursor:pointer}.option:hover:not(:disabled){border-color:var(--accent)}.option.correct{background:var(--ok-bg);border-color:var(--ok);color:var(--ok)}.option.wrong{background:var(--bad-bg);border-color:var(--bad);color:var(--bad)}.notice{margin:0;padding:8px 12px;border-radius:6px}.notice.ok{background:var(--ok-bg);color:var(--ok)}.notice.warn,.notice.error{background:var(--bad-bg);color:var(--bad)}:focus-visible{outline:2px solid var(--accent);outline-offset:2px}table{width:100%;border-collapse:collapse;display:block;overflow-x:auto}th,td{text-align:left;padding:6px 8px;border-bottom:1px solid var(--line)}.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}p{margin:0}