:root { color-scheme: light dark; --fg: #1d2330; --bg: #f6f7f9; --card: #ffffff; --line: #d9dde3; --link: #1f5fbf; }
@media (prefers-color-scheme: dark) { :root { --fg: #e6e9ee; --bg: #14171c; --card: #1d2128; --line: #343a44; --link: #8ab4ff; } }
* { box-sizing: border-box; }
html, body { margin: 0; }
body { min-height: 100vh; display: flex; align-items: center; justify-content: center; padding: 16px;
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif; color: var(--fg); background: var(--bg); }
main { width: 100%; max-width: 520px; background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 24px; }
h1 { font-size: 1.3rem; margin: 0 0 12px; }
p { margin: 0 0 12px; }
p:last-child { margin-bottom: 0; }
a { color: var(--link); }
[hidden] { display: none !important; }