<!DOCTYPE html>
<html>
<head>
<style>
.center {
text-align: center;
border: 3px solid green;
}
</style>
</head>
<body>

<h2>Center Text</h2>

<div class="center">
<p>This text is centered.</p>
</div>

</body>
</html>

Center Text

This text is centered.