:root{--bg:#f6f7f9;--card:#fff;--ink:#111827;--mute:#6b7280;--line:#e5e7eb;--accent:#0f766e}
@media(prefers-color-scheme:dark){:root{--bg:#0f172a;--card:#1e293b;--ink:#f1f5f9;--mute:#94a3b8;--line:#334155;--accent:#2dd4bf}}
*{box-sizing:border-box}body{margin:0;font:15px/1.45 system-ui,sans-serif;background:var(--bg);color:var(--ink)}
header{display:flex;align-items:center;gap:10px;padding:12px 16px;background:var(--card);border-bottom:1px solid var(--line);position:sticky;top:0}
header img{width:28px;height:28px}header h1{font-size:17px;margin:0;flex:1}
nav{display:flex;gap:4px;padding:8px 12px;overflow-x:auto}nav button{border:0;background:none;color:var(--mute);padding:8px 12px;border-radius:8px;font:inherit;cursor:pointer;white-space:nowrap}
nav button.on{background:var(--accent);color:#fff}
main{padding:0 12px 40px;max-width:900px;margin:auto}
.card{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:12px 14px;margin:8px 0}
.row{display:flex;justify-content:space-between;gap:8px;flex-wrap:wrap}.mute{color:var(--mute);font-size:13px}
.pill{font-size:12px;padding:2px 8px;border-radius:99px;background:var(--line)}
button.act,input,textarea,select{font:inherit;padding:8px 10px;border-radius:8px;border:1px solid var(--line);background:var(--card);color:var(--ink)}
button.act{background:var(--accent);color:#fff;border:0;cursor:pointer}
#chat{height:50vh;overflow-y:auto}.b{max-width:80%;padding:8px 12px;border-radius:14px;margin:6px 0}
.b.me{background:var(--accent);color:#fff;margin-left:auto}.b.ai{background:var(--line)}
form.line{display:flex;gap:6px}form.line input{flex:1}
#login{max-width:320px;margin:20vh auto;text-align:center}