<!DOCTYPE html>
<html>
<head>
<style>
div {
border: 2px solid;
padding: 10px;
background: #dddddd;
border-top-right-radius: 2em;
}
</style>
</head>
<body>
<div>The border-top-right-radius property allows you to add a rounded border to the top-right corner.</div>
</body>
</html>