:root {
  color-scheme: light dark;
  --fg: #1a1a1a;
  --bg: #fafafa;
  --muted: #6a6a6a;
  --accent: #2a4d8f;
}

@media (prefers-color-scheme: dark) {
  :root {
    --fg: #e8e8e8;
    --bg: #161616;
    --muted: #9a9a9a;
    --accent: #8ab1ff;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font: 16px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  color: var(--fg);
  background: var(--bg);
}

header, main, footer {
  max-width: 720px;
  margin: 0 auto;
  padding: 1.25rem 1.5rem;
}

header {
  border-bottom: 1px solid color-mix(in srgb, var(--fg) 12%, transparent);
  margin-bottom: 1rem;
}

header h1 {
  margin: 0 0 0.5rem;
  font-size: 1.6rem;
  letter-spacing: -0.01em;
}

nav a {
  color: var(--accent);
  text-decoration: none;
  margin-right: 1rem;
  font-size: 0.95rem;
}

nav a:hover { text-decoration: underline; }

article {
  margin-bottom: 2.25rem;
}

article h2 {
  font-size: 1.2rem;
  margin: 0 0 0.6rem;
}

article p {
  margin: 0 0 0.85rem;
}

footer {
  color: var(--muted);
  border-top: 1px solid color-mix(in srgb, var(--fg) 8%, transparent);
  font-size: 0.9rem;
  margin-top: 2rem;
}