:root { --bg:#0d1117; --card:#161b22; --text:#c9d1d9; --accent:#58a6ff; }
body { margin:0; background:var(--bg); color:var(--text); font-family:system-ui; }
main { max-width:800px; margin:0 auto; padding:16px; }
.card { background:var(--card); border:1px solid #30363d; border-radius:12px; padding:16px; }
label { display:block; margin:12px 0 6px; }
input, button { width:100%; padding:12px; border-radius:8px; border:1px solid #30363d; }
button { background:var(--accent); color:#041425; font-weight:600; cursor:pointer; }
.grid-2 { display:grid; grid-template-columns:1fr; gap:12px; }
@media (min-width:640px){ .grid-2{ grid-template-columns:1fr 1fr; } }