<div></div>

div {
  background: #2db34a;
  border-radius: 50%;
  height: 50px;
  position: absolute;
  width: 50px;

  animation: slide 2s ease-in-out .5s infinite alternate;
}

@keyframes slide {
  0% {
    left: 0;
    top: 0;
  }
  50% {
    left: 244px;
    top: 100px;
  }
  100% {
    left: 488px;
    top: 0;
  }
}