Edit in JSFiddle

$(".animate-easing").click(function(){
	$(this).toggleClass("active");
});
<div class="animate-easing"></div>
.animate-easing {
  cursor: pointer;
  width: 100px;
  height: 30px;
  background: #00BCD4;
  transition: all 1s ease 0s;
}
.animate-easing.active {
  width: 100%;
  background: #009688;
}