:root {
  --bg: #f5f3ff;
  --card: #fff;
  --ink: #2d2a45;
  --accent: #667eea;
  --ok: #2fa968;
  --bad: #e2574c;
  --muted: #8b86a8;
}
* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
/* #status 用 id 选择器设了 display:flex，会盖过 UA 的 [hidden]{display:none} */
[hidden] { display: none !important; }
body {
  margin: 0;
  font-family: -apple-system, 'PingFang SC', sans-serif;
  background: var(--bg);
  color: var(--ink);
  padding-bottom: 24px;
}
header { padding: 16px 16px 0; }
h1 { margin: 0 0 12px; font-size: 1.5rem; text-align: center; }
#tabs { display: flex; gap: 8px; }
.tab {
  flex: 1;
  min-height: 44px;
  border: none;
  border-radius: 10px;
  background: var(--card);
  color: var(--muted);
  font-size: 1rem;
  font-family: inherit;
}
.tab[aria-selected="true"] { background: var(--accent); color: #fff; }
main { padding: 16px; }

.cell {
  min-width: 44px;
  min-height: 44px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: none;
  border-radius: 10px;
  background: var(--card);
  color: var(--ink);
  font-size: 1.6rem;
  font-family: inherit;
  padding: 8px 4px;
}
.cell small { font-size: .7rem; color: var(--muted); margin-top: 2px; }
.cell:disabled { opacity: 0; pointer-events: none; }
.cell.playing { background: var(--accent); color: #fff; }

#status {
  position: fixed;
  left: 16px; right: 16px; bottom: 16px;
  min-height: 44px;
  display: flex; align-items: center; justify-content: center;
  background: var(--ink); color: #fff;
  border-radius: 10px; padding: 12px;
}

/* 音频诊断条。平时不显示，出问题（或 ?debug=1）才贴到屏幕最底下。 */
#audiodiag {
  position: fixed;
  left: 0; right: 0; bottom: 0;
  padding: 4px 8px;
  font-size: 0.7rem; line-height: 1.3;
  text-align: center; word-break: break-all;
  background: var(--bad); color: #fff;
}

/* ?debug=1 的自检面板，贴在诊断条上面。 */
#selftest {
  position: fixed;
  left: 0; right: 0; bottom: 24px;
  padding: 8px;
  background: var(--ink); color: #fff;
  font-size: 0.8rem;
  display: flex; flex-direction: column; gap: 6px;
}
#selftest button {
  min-height: 44px;
  font-size: 0.9rem;
  border: 0; border-radius: 8px;
  background: var(--accent); color: #fff;
}

.group { margin-bottom: 24px; }
.group h2 { font-size: 1rem; color: var(--muted); margin: 0 0 8px; font-weight: 600; }
.sm-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 8px; }
/* 末列 2.9rem：.cell 的 min-width 是 44px，轨道窄于它会溢出 */
.ym-row { display: grid; grid-template-columns: 2.4rem repeat(4, 1fr) 2.9rem; gap: 6px; margin-bottom: 8px; align-items: stretch; }
.ym-label { display: flex; align-items: center; color: var(--muted); font-size: 1.1rem; }
.play-all { font-size: 1rem; background: #ece9ff; }

.quiz-bar { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.scope { min-height: 44px; border-radius: 10px; border: none; background: var(--card); color: var(--ink); font-size: 1rem; padding: 0 10px; font-family: inherit; }
.meter { color: var(--muted); font-size: .85rem; }
.replay { width: 100%; min-height: 56px; border: none; border-radius: 12px; background: var(--accent); color: #fff; font-size: 1.1rem; font-family: inherit; margin-bottom: 16px; }
.opt-grid { display: grid; grid-template-columns: repeat(var(--cols, 3), 1fr); gap: 10px; }
.opt { min-height: 60px; font-size: 1.5rem; }
.opt.ok { background: var(--ok); color: #fff; }
.opt.bad { background: var(--bad); color: #fff; }
.next { width: 100%; min-height: 52px; margin-top: 16px; border: none; border-radius: 12px; background: var(--ink); color: #fff; font-size: 1.05rem; font-family: inherit; }

.tone-plot { width: 100%; height: 140px; background: var(--card); border-radius: 12px; display: block; margin: 12px 0; }
.plot-legend { display: flex; gap: 16px; font-size: .8rem; color: var(--muted); justify-content: center; }
.plot-legend i { display: inline-block; width: 18px; height: 3px; vertical-align: middle; margin-right: 5px; }
.plot-legend .ref i { background: #b8b2d8; }
.plot-legend .me i { background: #667eea; }

.shadow { text-align: center; }
.target { font-size: 4rem; margin: 8px 0 16px; }
.mic { width: 160px; height: 160px; border-radius: 50%; border: none; background: var(--accent); color: #fff; font-size: 1.1rem; font-family: inherit; margin: 8px 0 16px; }
.mic.recording { background: var(--bad); transform: scale(1.05); }
.mic:disabled { background: var(--muted); font-size: .9rem; padding: 0 16px; width: auto; min-width: 160px; min-height: 60px; height: auto; border-radius: 12px; }
.stars { font-size: 1.5rem; color: #f5a623; letter-spacing: 2px; }
.comment { font-size: 1.1rem; margin: 8px 0; }
.playback { display: flex; gap: 10px; }
.playback button { flex: 1; min-height: 48px; border: none; border-radius: 10px; background: var(--card); color: var(--ink); font-size: 1rem; font-family: inherit; }
.shadow-nav { display: flex; gap: 10px; margin-top: 20px; }
.shadow-nav button { flex: 1; min-height: 48px; border: none; border-radius: 10px; background: var(--card); color: var(--ink); font-size: 1rem; font-family: inherit; }
.debug { text-align: left; font-family: ui-monospace, monospace; font-size: .75rem; background: #1e1b33; color: #9ff; padding: 10px; border-radius: 8px; white-space: pre; overflow-x: auto; margin-top: 12px; }

#voicebar { display: flex; align-items: center; gap: 8px; margin-bottom: 10px; }
#voicebar label { font-size: .82rem; color: var(--muted); }
#voicebar select {
  min-height: 36px; border: none; border-radius: 9px;
  background: var(--card); color: var(--ink);
  font-size: .95rem; font-family: inherit; padding: 0 10px;
}