<img src="https://images.unsplash.com/photo-1480094751578-479ff3241555?ixlib=rb-0.3.5&q=80&fm=jpg&crop=entropy&cs=tinysrgb&w=1080&fit=max&s=4ac0c5a928fa35a4a58e660a7e8fd5ac" alt="" />
body{
  padding: 10px;
  background-color: rgb(230,230,230);
}
img{
  border-radius: 50%;
  width: 100px;
  height: 100px;
  position: relative;
  display: block;
  margin: 0 auto;
  border: thin solid orange;
  animation-name: cos;
  animation-duration: 1s;
  animation-delay: 3s;
  animation-timing-function:ease-in ;
  animation-direction: alternate ;
  animation-iteration-count: infinite;
}
@keyframes cos {
  0% {top: 0px}
  100% {top: 150px}
}

External CSS

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External JavaScript

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