Good question. This is probably a hole in all the present style sheets.
The DynamicWindow class (eventually) creates all parts of Leo's main window. So if we are comfortable with "Read the sources, Luke" you can discover the answers. You will find dw.createFindDockOrTab and dw.createSpellDockOrTab.
dw.createSpellTab and dw.createFindTab create the various frames, etc. The various helper methods assign object names to the components, so you can style these independently, if you really want to.
Let me know if these aren't enough clues.
Edward