style.css

html{height:100%;}
body {
background:#0D343A;
/*background:-webkit-gradient(linear,0% 0%,0% 100%, from(rgba(13,52,58,1) ), to(#000000));*/
/*background: -moz-linear-gradient(top, rgba(13,52,58,1) 0%, rgba(0,0,0,1) 100%);*/

overflow:hidden;
}
.t-0 {
   top: 35%;
    /* left: 50%; */
    font-size: 5em;
    z-index: 100;
    width: 40%;
    text-align: center;
    margin-left: 30%;
     box-shadow: 0 3px 6px rgba(0,0,0,0.16), 0 3px 6px rgba(0,0,0,0.23);
}
#demo {
  background: white;
  position: absolute;
}
.modal-content {
  background: transparent;
  border: none;
}
#captain_img {
  display: none;
  position: absolute;
  top: 35%;
  left: 25%;
  width: 50%;
}
.drop {
  background: url('test.svg');
  background-size: cover;
  background-position: center;
  width:150px;
  height:150px;
  position: absolute;
  /*background: red;*/
  bottom:200px;
  -webkit-animation: fall .63s linear infinite;
  -moz-animation: fall .63s linear infinite;  
}

/* animate the drops*/
@-webkit-keyframes fall {
  to {margin-top:900px;}
}
@-moz-keyframes fall {
  to {margin-top:900px;}
}