.zoom {
  float: left;
  padding: 0;
  background-color: red;
  transition: transform .2s; /* Animation */
  width: 30%;
  height: auto;
  margin: 0 auto;
}

.zoom:hover {
  transform: scale(1.5); /* (150% zoom - Note: if the zoom is too large, it will go outside of the viewport) */
}