* {
  box-sizing: border-box;
}

body {
  font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  line-height: 1.6;
  color: #1a1a1a;
  background: #f8f9fa;
  margin: 0;
  padding: 2rem;
  max-width: 48rem;
  margin-left: auto;
  margin-right: auto;
}

main {
  background: #fff;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 1px 3px rgba(0,0,0,.08);
}

h1 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.intro {
  color: #555;
  margin-bottom: 2rem;
}

h2 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.modules {
  list-style: none;
  padding: 0;
  margin: 0;
}

.modules li {
  padding: 0.5rem 0;
  border-bottom: 1px solid #eee;
}

.modules li:last-child {
  border-bottom: none;
}

.modules a {
  color: #0066cc;
  text-decoration: none;
}

.modules a:hover {
  text-decoration: underline;
}

.modules a:focus {
  outline: 2px solid #0066cc;
  outline-offset: 2px;
}