<!DOCTYPE html>
<html>
<head>
<style>
hr {
display: block;
margin-top: 0.5em;
margin-bottom: 0.5em;
margin-left: auto;
margin-right: auto;
border-style: inset;
border-width: 1px;
}
</style>
</head>
<body>
<p>A hr element is displayed like this:</p>
<hr>
<p>Change the default CSS settings to see the effect.</p>
</body>
</html>