<!DOCTYPE html>
<html>
<head>
<style>#myDIV {
width: 300px;
height: 300px;
background-image: url("paper.gif");
}
</style>
</head>
<body>
<p>Click the "Try it" button to set the background-image property of the DIV element to "smiley.gif":</p>
<button onclick="myFunction()">Try it</button>
<div id="myDIV">
<h1>Hello</h1>
</div>
<script>
function myFunction() {
document.getElementById("myDIV").style.backgroundImage = "url(smiley.gif)";
}
</script>
</body>
</html>