html, body {height:100%; }

  body{
    height: auto;
    background: url(image/sfondo-2.jpg) no-repeat center center fixed;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
  }


  .iscrizione {
    font-family:"Roboto";
    text-align: center;
    position: relative;
    margin-left: -300px;
    margin-top:15%;
    top:50%;
    left:50%;
    background-color: rgba(115, 165, 249, 0.75);
    color: #FFFFFF;
    width: 600px;
    padding: 10px;
    border-radius: 5px;
    margin-bottom: 10px;
    box-sizing: border-box;
  }

  .col{
    float: left;
    width: 50%;
  }

  .col span {
    display: block;
    margin: 16px;
  }

  .row {
    margin-bottom: 15px;
  }

  .row:after {
    content: "";
    display: table;
    clear: both;
  }

  .titolo{
    line-height: 20px;
    font-weight: 500;
    font-style: normal;
    font-size: 37px;
  }


  .button{
    background-color: #3d5ba1;
    color: #FFFFFF;
    font-weight: bold;
    margin: 10px auto 10px auto;
    min-width: 200px;
    padding: 10px 10px;
    display: inline-block;
    text-decoration: none;
    border: 1px solid #fff;
    font-size: 13px;

    }

  @media only screen and (max-width: 768px) {
  /* For mobile phones: */
   .col{
     float: none;
     width:auto;
   }
   .iscrizione{
     width: 90%;
     margin-left: 5%;
     left: 0;
     margin-top:5%;
     padding: 5px 5px;
   }
   .titolo{
     line-height: 50px;
   }

   body{
     height: auto;
     background: url(image/sfondo-2.jpg) no-repeat center center fixed;
     -webkit-background-size: cover;
     -moz-background-size: cover;
     -o-background-size: cover;
     background-size: auto;
   }
}