html { 
  background: url(https://img.freepik.com/free-vector/silver-background-with-snowflakes_1048-15.jpg?size=338&ext=jpg) no-repeat center center fixed; 
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}
h1 { text-align: center; 
 font-size: 80px;
color: #DC143C;
  font-weight: bold;
  <style> 
div {
    width: 100px;
    height: 100px;
    background: red;
    position: relative;
    -webkit-animation: mymove 5s infinite; /* Safari 4.0 - 8.0 */
    animation: mymove 5s infinite;
}

/* Safari 4.0 - 8.0 */
@-webkit-keyframes mymove {
    from {left: 0px;}
    to {left: 200px;}
}

@keyframes mymove {
    from {left: 0px;}
    to {left: 200px;}
}
</style>