x
<html><style>.democlass { color: red;}</style><body><h1 id="myH1">The Element Object</h1><h2>The setAttribute() Method</h2><p>Click "Add Class" to add a class attribute to the h1 element:</p><button onclick="myFunction()">Add Class</button><script>function myFunction() { document.getElementById("myH1").setAttribute("class", "democlass"); }</script></body></html>