:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --fg: #1c1f24;
  --muted: #5b6370;
  --accent: #1f5fd6;
  --card: #f4f6f9;
  --border: #e1e5eb;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111418;
    --fg: #e6e9ee;
    --muted: #9aa3b0;
    --accent: #7aa7ff;
    --card: #1a1f25;
    --border: #2a313a;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

header, main, footer {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 20px;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-top: 20px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border);
}

header .brand {
  font-weight: 700;
  color: var(--fg);
  text-decoration: none;
}

nav a { margin-left: 16px; }

a { color: var(--accent); }

main { padding-top: 24px; padding-bottom: 48px; }

h1 { font-size: 2rem; line-height: 1.25; margin: 0.5em 0; }
h2 { font-size: 1.3rem; margin-top: 2em; }
h3 { font-size: 1.05rem; margin-top: 1.5em; }

.lead { font-size: 1.15rem; color: var(--muted); }
.meta { color: var(--muted); font-size: 0.9rem; }

.notice {
  background: var(--card);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: 6px;
  padding: 12px 16px;
}

blockquote {
  margin: 0.5em 0;
  padding: 8px 16px;
  background: var(--card);
  border-radius: 6px;
}

footer {
  padding-top: 20px;
  padding-bottom: 40px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.9rem;
}

footer a { margin-right: 16px; }