PSEUDO-ELEMENT

Run
<!DOCTYPE html>
<html>
<head>
	<title>CSS Pseudo-element</title>
	<style>
		::selection {
		  color: red;
		  background: yellow;
		}
	</style>
</head>
<body>
    <h3>Drag the mouse over the paragraph.</h3>
	<p>This is first paragraph.</p>
	<p>This is second paragraph.</p>
</body>
</html>