.video-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;transition:transform .15s,box-shadow .15s;overflow:hidden}.video-card:active{transform:scale(.98)}.video-card:hover{box-shadow:0 4px 12px #00000014}.video-card-thumb{aspect-ratio:16/9;background:var(--border);position:relative}.video-card-thumb img{object-fit:cover;width:100%;height:100%;display:block}.video-card-duration{color:#fff;background:#000000bf;border-radius:4px;padding:2px 6px;font-family:monospace;font-size:.75rem;position:absolute;bottom:6px;right:6px}.video-card-body{padding:10px 12px 12px}.video-card-learn{color:var(--text);-webkit-line-clamp:3;-webkit-box-orient:vertical;margin-bottom:6px;font-size:.9rem;line-height:1.4;display:-webkit-box;overflow:hidden}.video-card-tag{color:var(--accent);background:var(--accent-bg);border-radius:20px;padding:2px 8px;font-size:.75rem}.watch-bar{background:var(--surface);border-bottom:1px solid var(--border);align-items:center;gap:10px;padding:8px 16px;display:flex}.watch-bar-track{background:var(--border);border-radius:3px;flex:1;height:6px;overflow:hidden}.watch-bar-fill{background:var(--accent);border-radius:3px;height:100%;transition:width .3s}.watch-bar.near .watch-bar-fill,.watch-bar.over .watch-bar-fill{background:var(--warn)}.watch-bar-label{color:var(--muted);white-space:nowrap;font-size:.8rem}.watch-bar-limit{opacity:.6}.watch-bar.over .watch-bar-label{color:var(--warn)}.home{min-height:100vh}.home-header{background:var(--bg);padding:16px 16px 8px}.home-header h1{color:var(--text);font-size:1.4rem}.topic-banner{background:var(--accent-bg);border:1px solid var(--accent);border-radius:var(--radius);color:var(--accent);margin:8px 16px;padding:8px 14px;font-size:.9rem}.category-nav{scrollbar-width:none;-webkit-overflow-scrolling:touch;gap:8px;padding:10px 16px;display:flex;overflow-x:auto}.category-nav::-webkit-scrollbar{display:none}.category-btn{background:var(--surface);border:1px solid var(--border);color:var(--muted);white-space:nowrap;font-size:.85rem;font-family:var(--font);border-radius:20px;min-height:36px;padding:6px 14px;transition:background .15s,color .15s}.category-btn.active{background:var(--text);border-color:var(--text);color:#fff}.video-grid{grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:14px;padding:12px 16px 32px;display:grid}.home-loading,.home-empty{text-align:center;color:var(--muted);padding:60px 16px;font-size:1rem}.player{background:#1a1a1a;flex-direction:column;min-height:100vh;display:flex}.player-topbar{background:#111;justify-content:space-between;align-items:center;padding:10px 16px;display:flex}.player-back{color:#ccc;font-size:1rem;font-family:var(--font);background:0 0;border:none;padding:8px 4px}.player-back:active{opacity:.7}.player-timer{color:#666;font-family:monospace;font-size:.8rem}.player-embed-wrap{background:#000;width:100%;padding-top:56.25%;position:relative}.player-embed{border:none;width:100%;height:100%;position:absolute;top:0;left:0}.player-info{background:#1a1a1a;padding:16px}.player-learn{color:#ccc;font-size:.95rem;line-height:1.5}:root{--bg:#f5f0e8;--surface:#fff;--border:#e8e2d6;--text:#2c2825;--muted:#8a7f74;--accent:#5a7a4a;--accent-bg:#eef3eb;--warn:#8a6a3a;--warn-bg:#fdf5e6;--radius:12px;--font:"Georgia", serif}*{box-sizing:border-box;margin:0;padding:0}body{background:var(--bg);color:var(--text);font-family:var(--font);-webkit-font-smoothing:antialiased;font-size:16px;line-height:1.5}html{scroll-behavior:smooth}button,a{cursor:pointer;min-height:44px}h1{font-size:1.6rem;font-weight:400}h2{color:var(--muted);margin-bottom:.5rem;font-size:1.2rem;font-weight:400}