<csstest def="Classes: XHTML global class attribute" module="W3C Selectors" modulename="css3-modsel" number="171" rev="1.0" date="20-september-2002" xmlns="http://www.example.org/css3tests">

<author>Ian Hickson</author>

<cssrules>
 p { color: green; }
 .fail { color: red; }
</cssrules>

<code>
   <p xmlns="http://www.w3.org/1999/xhtml" xmlns:xhtml="http://www.w3.org/1999/xhtml">
    <span xhtml:class="fail">This should be green.</span>
   </p>
</code>

</csstest>