.sprite.e-ball{
      width: 100%;
      height: 128px;
      background-image : url(idle.png);
      animation: moveY-ball 1s steps(4) infinite;
      background-position: 50% 0;
    }
@keyframes moveY-ball{
  from{background-position-y:0px;}
  to{background-position-y:-386px;}
}