:root{--bg:#fafafa;--fg:#1a1a1a;--muted:#737373;--line:#e5e5e5;--card:#fff;--accent:#1a1a1a;--on-accent:#fff}
@media (prefers-color-scheme:dark){:root{--bg:#0a0a0a;--fg:#fafafa;--muted:#a3a3a3;--line:#2e2e2e;--card:#1a1a1a;--accent:#fafafa;--on-accent:#0a0a0a}}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;min-height:100dvh;display:flex;flex-direction:column;background:var(--bg);color:var(--fg);
  font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;line-height:1.4}
.bo{font-family:"Noto Serif Tibetan","Noto Sans Tibetan","Kailasa","Jomolhari","Microsoft Himalaya",serif;line-height:1.7}
a{color:inherit}
header,footer{padding:14px 16px;text-align:center;color:var(--muted);font-size:14px}
header a,footer a{text-decoration:none}
main{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:20px;padding:8px 16px 24px;text-align:center}
.letter{font-size:clamp(96px,34vw,180px);line-height:1.5;margin:0}
.word{font-size:clamp(30px,9vw,44px);margin:0}
.en{color:var(--muted);margin:0;font-size:16px}
.play{width:112px;height:112px;border-radius:50%;border:0;background:var(--accent);color:var(--on-accent);
  display:grid;place-items:center;cursor:pointer;-webkit-tap-highlight-color:transparent;transition:transform .12s}
.play:active{transform:scale(.94)}
.play:focus-visible,a:focus-visible{outline:3px solid var(--muted);outline-offset:4px}
.play svg{width:44px;height:44px;fill:currentColor}
.play .stop,.play.on .go{display:none}
.play.on .stop{display:block}
.hint{color:var(--muted);font-size:14px;margin:0;min-height:20px}
nav{display:flex;justify-content:space-between;align-items:center;gap:8px;width:100%;max-width:420px;margin-top:8px}
nav a{flex:1;padding:14px 8px;border:1px solid var(--line);border-radius:14px;background:var(--card);text-decoration:none;font-size:22px}
nav a.all{flex:0 0 auto;font-size:14px;padding:14px 16px;color:var(--muted)}
nav span{flex:1}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(72px,1fr));gap:10px;width:100%;max-width:560px}
.grid a{aspect-ratio:1;display:grid;place-items:center;border:1px solid var(--line);border-radius:14px;background:var(--card);text-decoration:none;font-size:34px}
h1{font-size:clamp(24px,7vw,34px);margin:0;font-weight:600}
.btn{display:inline-block;padding:14px 22px;border-radius:14px;background:var(--accent);color:var(--on-accent);text-decoration:none}