:root { color-scheme: light dark; --bg: #ffffff; --fg: #0b1f33; }
@media (prefers-color-scheme: dark) { :root { --bg: #0b1f33; --fg: #f2f5f8; } }
html, body { margin: 0; height: 100%; }
body {
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
  display: grid;
  place-items: center;
  padding: 0 16px;
}
h1 { font-size: 2rem; margin: 0 0 0.5rem; }
p { margin: 0; opacity: 0.8; }