By default report a transformed explain as css class explain and the x-context parameter as a class, always generate a content wrapping div (-> htmlpagetable), allow specializations to add a class (or more) by setting/superseding a variable. Use this for glossary-explain, generate a css background from a picture ref in tei:front, enable adding an alpha channel to this background using css. Move sampleText.css to be only inserted by profiel.xsl.