body {
  font-family: system-ui, sans-serif;
  margin: 0;
  padding: 2rem;
  line-height: 1.6;
  background: #fff;
  color: #222;
}
header, footer {
  margin-bottom: 2rem;
}
nav a {
  margin-right: 1rem;
  text-decoration: none;
  color: #005f99;
}