<rules
    xmlns="http://namespaces.plone.org/diazo"
    xmlns:css="http://namespaces.plone.org/diazo/css"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    >

    <drop
        css:if-content="#nothing"
        attributes="id"
        css:theme="#alpha"
        />

</rules>
