body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: #f5f5f5;
    color: #333;
  }
  header, footer {
    background: #004466;
    color: #fff;
    text-align: center;
    padding: 1rem 0;
  }
  nav {
    background: #006699;
    padding: 0.5rem;
    text-align: center;
  }
  nav a {
    color: #fff;
    margin: 0 1rem;
    text-decoration: none;
  }
  main {
    padding: 2rem;
    text-align: center;
  }