:root { color-scheme: dark; }
body { font-family: ui-monospace, monospace; background: #0f172a; color: #10b981;
       display: grid; place-items: center; min-height: 100vh; margin: 0; text-align: center; }
a { color: #38bdf8; }
small { color: #64748b; }
.error { color: #f87171; }