body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    text-align: center;
  }
  header {
    background: #333;
    color: #fff;
    padding: 1em;
  }
  header select {
    margin-top: 1em;
    padding: 0.5em;
  }
  main {
    padding: 2em;
  }
  footer {
    background: #333;
    color: #fff;
    padding: 1em;
    position: fixed;
    bottom: 0;
    width: 100%;
  }