<!DOCTYPE html>
<html>
<head>
<style>
[class^="test"] {
background: #ffff00;
}
</style>
</head>
<body>
<div class="first_test">The first div element.</div>
<div class="second">The second div element.</div>
<div class="test">The third div element.</div>
<p class="test">This is some text in a paragraph.</p>
</body>
</html>