:root{--bg: #f6f7f9;--surface: #ffffff;--ink: #14181f;--muted: #5f6b7a;--line: #d9dee5;--accent: #1e88e5;color-scheme:light dark;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif}@media(prefers-color-scheme:dark){:root{--bg: #14181f;--surface: #1d232c;--ink: #e8ecf1;--muted: #9aa6b4;--line: #2c3440}}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink)}a{color:var(--accent)}.page{max-width:960px;margin:0 auto;padding:16px}.header{display:flex;align-items:center;justify-content:space-between;gap:12px;max-width:960px;margin:0 auto;padding:12px 16px}.brand{font-weight:700;font-size:18px;color:var(--ink);text-decoration:none}.drill-list{list-style:none;padding:0;display:grid;gap:8px}.drill-list a{display:block;padding:12px 14px;background:var(--surface);border:1px solid var(--line);border-radius:10px;text-decoration:none;color:var(--ink)}.drill-list small{color:var(--muted);display:block;margin-top:2px}.player{display:grid;gap:8px;background:var(--bg)}.player-stage{position:relative;height:min(70vh,560px);border-radius:10px;overflow:hidden}.player:fullscreen .player-stage{height:calc(100vh - 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