* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  color-scheme: light dark;
  --bg: #fff;
  --text: #222;
  --heading: #111;
  --heading-secondary: #333;
  --link: #0066cc;
  --link-hover: #004499;
  --border: #ddd;
  --muted: #777;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000;
    --text: #e0e0e0;
    --heading: #fff;
    --heading-secondary: #f0f0f0;
    --link: #4da6ff;
    --link-hover: #fff;
    --border: #333;
    --muted: #888;
  }
}

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 15px;
  line-height: 1.7;
  padding: 20px 16px 40px;
  max-width: 720px;
  margin: 0 auto;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--heading);
  margin-bottom: 8px;
  line-height: 1.3;
}

h2 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--heading);
  margin-top: 32px;
  margin-bottom: 8px;
  line-height: 1.3;
}

h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--heading-secondary);
  margin-top: 24px;
  margin-bottom: 6px;
}

h4 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--heading-secondary);
  margin-top: 16px;
  margin-bottom: 4px;
}

p {
  margin-bottom: 14px;
}

ul, ol {
  margin: 10px 0 14px 20px;
}

li {
  margin-bottom: 8px;
}

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

a:hover {
  color: var(--link-hover);
  text-decoration: underline;
}

hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 32px 0;
}

.last-updated {
  margin-top: 32px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--muted);
}

@media (min-width: 600px) {
  body {
    font-size: 16px;
    padding: 40px 24px 60px;
  }

  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.4rem;
  }
}