@keyframes bounce {
  0% {
    width: 0;
    height: 0;
    top: 19px;
    left: 19px;
  }

  50% {
    width: 38px;
    height: 38px;
    top: 0;
    left: 0;
  }

  100% {
    width: 0;
    height: 0;
    top: 19px;
    left: 19px;
  }
}