Allow pressed (and/or toggled) buttons to have a color tint, either - None (like currently) - Selected background tinting the background color (slight tint, as the default button admits) - Selected background as background color (as the default button also admits) - Custom color as background (as can be defined for progress bars, for example) - Selected background as border color (as the default button also admits) - Button text color as border (as the default button also admits) This way qtcurve will be able to adapt to some "modern" themes or trends, have more flexibility and also more "legibility", as toggled buttons on toolbars will be able to stand out much more.