<html>
<head>
<style type="text/css">
[lang=en] { color: red }
</style>
</head>
<body>
    <h1>Html Heading</h1>
    <p lang="fr">fzz</p>
    <h2>Html Heading</h2>
    <p lang="en-us">fzz</p>
    <p lang="en">fzz todo doesnt work</p>
</body>
</html>