:root {
  color-scheme: light;
  --text: #172b4d;
  --muted: #5e6c84;
  --bg: #f7f8fa;
  --card: #ffffff;
  --border: #dfe1e6;
  --accent: #0052cc;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  padding: 20px 24px;
}

header nav {
  max-width: 760px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

header nav .brand {
  font-weight: 700;
  font-size: 18px;
  color: var(--text);
  text-decoration: none;
}

header nav .links a {
  margin-left: 20px;
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
}

header nav .links a:hover {
  color: var(--accent);
}

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 24px 80px;
}

h1 {
  font-size: 28px;
  margin-bottom: 4px;
}

.updated {
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 32px;
}

h2 {
  font-size: 18px;
  margin-top: 32px;
  margin-bottom: 8px;
}

p, li {
  color: var(--text);
  font-size: 15px;
}

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

ul { padding-left: 20px; }

footer {
  text-align: center;
  color: var(--muted);
  font-size: 13px;
  padding: 24px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 24px;
  margin-bottom: 16px;
}