<html>
<head>
<style>
:dir(rtl) {
background-color: lightgreen;
}
</style>
</head>
<body>
<h1>Demo of :dir()</h1>
<p>This is some text in a pragraph.</p>
<p dir="rtl">Write this text right-to-left!</p>
<p>This is some text in a pragraph.</p>
</body>
</html>