/*body
{
 background-image: url(bg.png) 
}*/
body
{
 background-image: url(bg.png);
 background-size: 10%;
 animation: slide 9000000s linear infinite;
}
@keyframes slide{
0% {
background-position: 0% 0%;
}
50% {
background-position: 2000000% 4000000%;
}
100% {  
background-position: 0% 100%;
}
}