body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  max-width: 42rem;
  margin: 3rem auto;
  padding: 0 1.25rem;
  line-height: 1.6;
  color: #1f2328;
}
h1 { font-size: 1.6rem; margin-bottom: 0.25rem; }
h2 { font-size: 1.15rem; margin-top: 2rem; }
.updated { color: #656d76; font-size: 0.9rem; margin-top: 0; }
nav { margin-top: 3rem; padding-top: 1rem; border-top: 1px solid #d0d7de; font-size: 0.9rem; }
nav a { margin-right: 1rem; }
a { color: #0969da; }