body {
      font-family: Arial, sans-serif;
      background-color: #f4f4f4;
      margin: 0;
      padding: 0;
    }

    header {
      background-color: #333;
      color: #fff;
      text-align: center;
      padding: 1em;
    }

    nav {
      display: flex;
      justify-content: center;
      background-color: #666;
      padding: 0.5em;
    }

    nav a {
      color: #fff;
      text-decoration: none;
      margin: 0 1em;
      font-weight: bold;
    }

    nav a:hover {
      text-decoration: underline;
    }

    main {
      max-width: 800px;
      margin: 20px auto;
      padding: 20px;
      background-color: #fff;
      border-radius: 8px;
      box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    }

    footer {
      text-align: center;
      padding: 1em;
      background-color: #333;
      color: #fff;
    }