:root {
  --bg: #f6f5f1; --fg: #1d1f22; --muted: #5d6166; --card: #ffffff; --line: #d9d7d0;
  --accent: #1f6f5c; --accent-fg: #ffffff; --warn: #9a4a12; --ok: #1f6f5c;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #16181b; --fg: #e8e6e1; --muted: #a2a6ab; --card: #202327; --line: #33373c;
          --accent: #4fb39a; --accent-fg: #0d1512; --warn: #e0a06a; --ok: #6fcfb5; }
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); color: var(--fg); overflow-x: hidden; }
body { font: 16px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, "Noto Sans", sans-serif; max-width: 640px;
       margin: 0 auto; padding: 0 16px 32px; }
header { position: sticky; top: 0; background: var(--bg); display: flex; align-items: center; gap: 8px;
         padding: 10px 0; border-bottom: 1px solid var(--line); z-index: 2; }
nav { display: flex; gap: 4px; flex: 1; min-width: 0; }
nav button { flex: 1 1 auto; min-width: 0; padding: 8px 6px; border: 0; border-radius: 8px; background: transparent;
             color: var(--muted); font: inherit; font-size: 15px; }
nav button[aria-selected="true"] { background: var(--card); color: var(--fg); font-weight: 600; }
.pill { font-size: 12px; padding: 2px 8px; border-radius: 999px; border: 1px solid var(--line); color: var(--muted);
        white-space: nowrap; }
.pill.on { color: var(--ok); border-color: var(--ok); }
h2 { font-size: 17px; margin: 20px 0 8px; }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.row { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin: 10px 0; }
button { font: inherit; padding: 10px 14px; border-radius: 10px; border: 1px solid var(--line); background: var(--card);
         color: var(--fg); min-height: 44px; }
button.primary { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); }
button:disabled { opacity: .5; }
.seg { display: inline-flex; gap: 6px; align-items: center; padding: 6px 10px; border: 1px solid var(--line);
       border-radius: 10px; background: var(--card); }
ul.plan, ol.queue { padding: 0; margin: 0; list-style: none; }
.plan li, .queue li { padding: 10px 0; border-bottom: 1px solid var(--line); overflow-wrap: anywhere; }
.queue li { display: grid; grid-template-columns: 1fr auto; gap: 2px 8px; }
.queue .t { font-weight: 600; }
.queue .m { color: var(--muted); font-size: 13px; grid-column: 1 / -1; }
.queue button { grid-row: 1 / span 2; grid-column: 2; align-self: center; }
.tag { font-size: 12px; padding: 1px 6px; border-radius: 6px; border: 1px solid var(--line); }
.tag.below { color: var(--warn); border-color: var(--warn); }
.tag.tts { color: var(--muted); }
.now { font-weight: 600; overflow-wrap: anywhere; }
#media-box video, #media-box audio { width: 100%; max-width: 100%; border-radius: 10px; background: #000; }
#media-box audio { background: transparent; }
.controls button { flex: 1; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 12px; margin: 12px 0; }
.zh { font-size: 20px; line-height: 1.6; overflow-wrap: anywhere; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 8px 0; }
.chips button { font-size: 20px; padding: 6px 12px; }
.q { margin: 0 0 8px; font-weight: 600; }
.choice { display: block; width: 100%; text-align: left; margin: 6px 0; }
.choice.right { border-color: var(--ok); color: var(--ok); }
.choice.wrong { border-color: var(--warn); color: var(--warn); }
dl.stats { display: grid; grid-template-columns: auto 1fr; gap: 6px 12px; }
dl.stats dt { color: var(--muted); }
dl.stats dd { margin: 0; overflow-wrap: anywhere; }