.site-header {
  max-width: 900px;
  margin: 4rem auto 3rem auto;
  padding: 0 1rem;
}

.site-header h1 {
  font-size: 2.6rem;
  margin-bottom: 0.5rem;
}

.subtitle {
  font-size: 1.1rem;
  color: #444;
}

.doc-container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 1rem 4rem 1rem;
}

section {
  margin-top: 3rem;
}

.site-footer {
  border-top: 1px solid #ddd;
  margin-top: 4rem;
  padding: 2rem 1rem 3rem 1rem;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
  font-size: 0.9rem;
  color: #444;
}

.footer-note {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: #666;
}