:root {
  --text-color: #222;
  --bg-color: #fff;
  --link-color: #0056b3;
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root { --text-color: #eee; --bg-color: #121212; --link-color: #66b0ff; }
}
body { font-family: var(--font-stack); color: var(--text-color); background: var(--bg-color); line-height: 1.6; margin: 0; padding: 1rem; max-width: 800px; margin: auto; }
header { margin-bottom: 2rem; }
footer { margin-top: 3rem; border-top: 1px solid #ccc; padding-top: 1rem; font-size: 0.9rem; }
nav a { margin-right: 1rem; color: var(--link-color); }
a { color: var(--link-color); text-decoration: none; }
h1, h2 { line-height: 1.2; }
input, button { display: block; margin: 1rem 0; padding: 0.5rem; font-size: 1rem; }
textarea { width: 100%; height: 100px; margin-top: 1rem; }
@media (prefers-reduced-motion: reduce) { *, ::before, ::after { animation-duration: 0.01ms !important; } }