div {
  margin-left: 50px;
  width: 200px;
  height: 200px;
  background-color: coral;
  Animation-name : fade ;
  Animation-delay : 2s;
  Animation-duration : 3s;
  Animation-iteration-count : infinite;
}

@keyframes fade {
  From {
    Opacity : 1;
  }
  To {
    Opacity : 0;
  }
}