Font color for buttons extension

I'm using the new VizLib Button extension (v 1.0.0) and it would be nice to control the font color at the individual button item level rather than at the global appearance level.  The use case being that perhaps you want to control the font color to align with the individual buttons active/inactive state.

In my specific example, my active button would have a darker blue background with a white font while the inactive state would be a white background and black (or darker gray) font.  If the font is set at white at the global level, you can't see the button text in the inactive state.