body {
    background-image: url("/img/bol/fondo.jpg");
    position: sticky;
  }
  
  header {
    color: black;
    background-color: rgba(255,255,255,0.75);
  }
  
  main {
    max-width: 1400px;
  }
  
  .ima {
    width: 1200px;
  }