:root { color-scheme: light dark; --bg: #f6f7fb; --fg: #1b1f2a; --muted: #5b6273; }
@media (prefers-color-scheme: dark) { :root { --bg: #11141c; --fg: #e8eaf1; --muted: #9aa3b5; } }
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: grid; place-items: center; background: var(--bg); color: var(--fg);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; padding: 16px; }
main { max-width: 520px; text-align: center; }
h1 { font-size: 2rem; margin: 0 0 .5rem; }
p { color: var(--muted); margin: 0; }
code { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: .9em; }