button-to-change.html

<!DOCTYPE html>
<html>
<head>
	<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
<meta charset=utf-8 />
<title>DOM Exercise 1 | W3Resource</title>
</head> 
<body>
<div class="container">
<p id ='text'>JavaScript Exercises - w3resource</p> 
<div>
<button class="btn btn-primary" id="jsstyle"
onclick="press()">Style</button>
</div>
</div>
<script type="text/javascript">
	el1 = document.getElementById('text');
	function press(){
 text.style.fontSize = "14pt";
 text.style.fontFamily = "Comic Sans MS";
 text.style.color = "green";
	}
</script>
</body>
</html>