body {
    font-family: Arial, 'Times New Roman', Times, serif;
    margin: 0;
    padding: 0;
    background-color: #f2f2f2;
  }
  
  header {
    background-color: #f70000;
    color: #fff;
    padding: 20px;
    text-align: center;
  }
  
  header .logo {
    width: 100px;
    height: auto;
    margin: 10px;
  }
  
  main {
    padding: 150px;
    text-align: center;
  }
  
  footer {
    background-color: #f70000;
    color: #fff;
    padding: 10px;
    text-align: center;
    clear: both;
  }
  
  .boton-comenzar {
      background-color: #f70000;
      color: #fff;
      padding: 10px 20px;
      border: none;
      border-radius: 5px;
      cursor: pointer;
      font-size: 18px;
    }
    
    .boton-comenzar:hover {
      background-color: #f70000;
    }