Tryit Editor v1.8

Source Code:

<!DOCTYPE html>
<html>
<head>
<style> 
div
{
border:2px solid;
padding:10px;
background:#dddddd;
border-top-right-radius:2em;
-webkit-border-top-right-radius:2em; /* Safari */
}
</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>

Result:

W3Schools.com - Try it yourself

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