<!DOCTYPE html>
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.2/jquery.min.js"></script>
<script>
$(document).ready(function(){
$("button").click(function(){
$("div").height(function(n,c){
return c+200;
});
});
});
</script>
</head>
<body>
<button>Increase height of div with 200 px</button><br><br>
<div style="height:100px;border:4px solid;"></div>
</body>
</html>