body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  line-height: 1.5;
}

header {
  border-bottom: 1px solid #ddd;
  padding: 0.5rem 1rem;
}

nav a {
  margin-right: 1rem;
  text-decoration: none;
}

main {
  max-width: 800px;
  margin: 2rem auto;
  padding: 0 1rem;
}