Other applications does not respect palette for background but Calligrasheets. Make default to white background with black text, when starts editing cell background is palette' one, text too.
Hmm, imo styling odf apps content area should be considdered a bug :=)
Because: All info pertaining to presentation of content is stored in odf file and is controllable by user, so styling it would often create strange resullts. (And it would not be much wysiwyg about it)
Of course everything else like tools, dialogs, window decorations can be styled.