:root{
  --bg:#ffffff;
  --fg:#1f2328;
  --muted:#5b646b;
  --brand:#0aa;
  --card:#f6f8fa;
  --border:#e5e7eb;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family: system-ui, -apple-system, Segoe UI, Roboto, PingFang SC, Microsoft YaHei, Arial, sans-serif;
  background:var(--bg); color:var(--fg);
  line-height:1.6;
}
.site-header{padding:24px 16px;text-align:center}
.site-header h1{margin:0 0 6px}
.subtitle{margin:0;color:var(--muted)}
.controls{display:flex;flex-wrap:wrap;gap:12px;align-items:center;padding:12px 16px;border-top:1px solid var(--border);border-bottom:1px solid var(--border);background:var(--card)}
.site-nav{display:flex;gap:12px;align-items:center;justify-content:center;padding:10px 16px;border-top:1px solid var(--border);border-bottom:1px solid var(--border);background:var(--bg)}
.site-nav a{color:var(--fg);text-decoration:none;padding:6px 10px;border-radius:8px;border:1px solid transparent}
.site-nav a:hover,.site-nav a:focus{border-color:var(--border);background:var(--card);outline:none}
.controls input[type="search"]{flex:1;min-width:220px;padding:8px 10px;border:1px solid var(--border);border-radius:6px}
.filters label{margin-right:8px;white-space:nowrap}
.grid{
  display:grid;
  grid-template-columns:repeat(auto-fill,minmax(96px,1fr));
  gap:12px;
  padding:16px;
}
.card{
  background:#fff;border:1px solid var(--border);border-radius:10px;
  padding:10px; text-align:center;
  display:flex;flex-direction:column;gap:6px;justify-content:center;align-items:center;
  transition:box-shadow .2s ease, transform .06s ease;
}
.card:hover{box-shadow:0 4px 18px rgba(0,0,0,.06);transform:translateY(-1px)}
.card .label{font-size:20px;font-weight:700;letter-spacing:.5px}
.card .meta{font-size:12px;color:var(--muted)}
.card .actions{display:flex;gap:6px}
button.play{
  border:1px solid var(--border); background:#fff;color:var(--fg);
  padding:6px 10px;border-radius:8px;cursor:pointer
}
button.play:hover{border-color:var(--brand);color:var(--brand)}
.download{padding:6px 16px 24px;color:var(--muted)}
.site-footer{padding:24px 16px;border-top:1px solid var(--border);text-align:center;color:var(--muted)}
/* 优化：筛选条吸顶、卡片与按钮更易点按、可见焦点与状态 */
.controls{position:sticky;top:0;background:var(--card);z-index:50;backdrop-filter:saturate(140%) blur(6px)}
.card{min-height:92px}
button.play{min-width:84px;min-height:36px}
:focus-visible{outline:2px solid var(--brand);outline-offset:2px}
.site-nav a[aria-current="page"]{border-color:var(--brand);background:rgba(0,170,170,.08)}
/* 轻量提示 */
.toast{position:fixed;left:50%;bottom:18px;transform:translateX(-50%);background:#111;color:#fff;padding:8px 12px;border-radius:8px;opacity:.96;box-shadow:0 4px 18px rgba(0,0,0,.18);z-index:9999;font-size:14px}
@media (max-width:480px){
  .grid{grid-template-columns:repeat(auto-fill,minmax(88px,1fr));gap:10px}
  .card .label{font-size:18px}
  button.play{min-width:76px}
}
@media (prefers-color-scheme: dark){
  :root{--bg:#0b0c0f;--fg:#e6e6e6;--muted:#9aa0a6;--card:#0f1115;--border:#22252b}
  .card,button.play{background:#0f1115}
  .site-nav a{color:var(--fg)}
}