css styling for gnome panel window list applet

["pauriem gmail com" <pauriem gmail com>]

I am trying to edit my gtk 3.0 theme css to change the appearance of
the gnome panel window list applet. The file already has selectors
like PanelApplet and WnckTasklist. The PanelApplet properties apply
partially to the window list ui apparently via inheritance but none of
the selectors I have tried (including also WnckApplet,
WindowListApplet, .window-button, .window-list-item-box) cause any
change in for instance the window label text color or the list
background color. I would be very grateful for any help finding docs
or the relevant source code showing what widgets the ui consists of
and what css selectors might affect them.