<!DOCTYPE html>
<html>
 <title>':lang()': inherit LANG from parent element</title>
 <style>
  p:lang(x) { background: green }
 </style>
 <div lang="x-test">
    <p>This line should have a green background.
    <p lang="y-test">This line should NOT have a green background.
 </div>
</html>