[Zope] Using of Structured Text with CSS

Hi! I want to use the <dtml-var xyz fmt=structured-text> Tag in connection with stylesheets (css). The problem is that the stylesheets take no effect when the structured-text is activated. The result is always standardtext without any stylesheets only with the elements of structured-text. Is there any possibility to use structured-text and stylesheets together. Bye Steffen