fori,
<!DOCTYPE HTML>
<html>
<meta charset="utf-8">
<body>
<div id="myDiv" ></div>
<style>
#myDiv {
width: 20vmin;
height: 20vmin;
background: green;
}
#myDiv:active {
background: blue;
}
</style>
<script>
let elem = document.getElementById("myDiv")
elem.addEventListener( "click" , function(event) {
elem.style.transition = "height 1s ease";
elem.style.height = Math.floor(Math.random() * 100) + "vmin";
});
elem.addEventListener( "transitionend" , function(event) {
elem.style.transition = "";
});
</script>
</body>
</html>