<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>Test iframe document</title>
<style>
.mark,
.lorem {
background: yellow;
}
</style>
<!-- The above is necessary to check if elements inside <head> will be ignored -->
</head>
<body>
<p>
Lorem ipsum testing dolor
</p>
</body>
</html>