body {
      font-family: Arial, sans-serif;
      margin: 20px;
    }
    button {
      padding: 10px 20px;
      margin: 5px;
      font-size: 16px;
      cursor: pointer;
    }
    .message {
      margin-top: 20px;
      font-size: 14px;
      color: green;
    }
    .error {
      color: red;
    }