<csstest def=":only-child pseudo-class" module="W3C Selectors" modulename="css3-modsel" number="36" rev="1.0" date="11-july-2001" xmlns:a="http://www.example.org/a" xmlns:b="http://www.example.org/b" xmlns:html="http://www.w3.org/1999/xhtml" xmlns="http://www.example.org/css3tests">

<author>Daniel Glazman</author>
<cssrules>.red { background-color : red }
p:only-child { background-color : lime }
div.testText &gt; div &gt; p { margin-left : 1em }
</cssrules>
<code>
<p xmlns="http://www.w3.org/1999/xhtml">This paragraph should have normal background</p>
<div xmlns="http://www.w3.org/1999/xhtml">This div contains only one paragraph
    <p class="red">This paragraph should have green background</p>
</div>
</code>
</csstest>