:root {
  --bg: #ffffff;
  --bg-elevated: #f7f7f7;
  --fg: #0f0f10;
  --fg-secondary: #4a4a52;
  --fg-tertiary: #8a8a92;
  --accent: #0a85ff;
  --rule: rgba(0, 0, 0, 0.08);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0a0a0c;
    --bg-elevated: #16161a;
    --fg: #f5f5f7;
    --fg-secondary: #b6b6c0;
    --fg-tertiary: #6e6e78;
    --accent: #4ea3ff;
    --rule: rgba(255, 255, 255, 0.08);
  }
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", system-ui, sans-serif;
  font-size: 17px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 64px 24px 96px;
}

header {
  border-bottom: 1px solid var(--rule);
  margin-bottom: 32px;
  padding-bottom: 24px;
}

header .brand {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--fg-tertiary);
}

header .brand a {
  color: inherit;
  text-decoration: none;
}

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

h1 {
  font-size: 36px;
  line-height: 1.15;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 8px 0 4px;
}

.last-updated {
  color: var(--fg-tertiary);
  font-size: 14px;
  margin: 0;
}

h2 {
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin: 40px 0 12px;
}

h3 {
  font-size: 17px;
  font-weight: 600;
  margin: 24px 0 8px;
}

p {
  color: var(--fg-secondary);
  margin: 12px 0;
}

ul {
  color: var(--fg-secondary);
  padding-left: 22px;
  margin: 12px 0;
}

li {
  margin: 6px 0;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

footer {
  margin-top: 64px;
  padding-top: 24px;
  border-top: 1px solid var(--rule);
  color: var(--fg-tertiary);
  font-size: 14px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

footer nav a {
  color: var(--fg-tertiary);
  margin-right: 16px;
}

footer nav a:last-child {
  margin-right: 0;
}