body {
  font-family: sans-serif;
  background: #f5f5f5;
  padding: 2rem;
}
h1 {
  text-align: center;
  margin-bottom: 2rem;
}
.module {
  background: white;
  padding: 1rem;
  border-radius: 8px;
  margin-bottom: 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}
pre {
  background: #f0f0f0;
  padding: 1rem;
  border-radius: 4px;
  overflow-x: auto;
}