body {
  font-family: Arial, sans-serif;
  margin: 0; padding: 0;
  background-color: #f5f5f5;
  color: #333;
}
header, footer {
  background-color: #004080;
  color: white;
  text-align: center;
  padding: 1rem;
}
nav a {
  margin: 0 1rem;
  color: white;
  text-decoration: none;
}
main {
  padding: 2rem;
}