.center {
    display: block;
    margin-left: auto;
    margin-right: auto;
    width: 50%;
  }
  body {
    background-image: url('https://SITE_URL/ico/background.png');
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-size: 100% 100%;
    text-align: center;
    color: white;
    font-family: Arial, Helvetica, sans-serif;
  }