<!DOCTYPE html>
<html>
<head>
<style>
#myDIV {
width: 500px;
height: 500px;
background-color: lightblue;
}
</style>
</head>
<body>
<p>Mouse over the DIV element to see what the cursor looks like.<p>
<p>Click the "Try it" button, and mouse over the DIV element again to see that the cursor has changed:</p>
<button onclick="myFunction()">Try it</button>
<div id="myDIV">
<h3>Mouse over me, and check out the mouse-cursor.</h3>
</div>
<script>
function myFunction() {
document.getElementById("myDIV").style.cursor = "not-allowed";
}
</script>
</body>
</html>