Qt Style Sheet Displaying Circular Shape

Hi All,
I have created a round Push Button Using Style Sheet. I have applied three states on it Normal ,Hover and Checked .On Each state the Color Changes.
However the Problem is that in the case of hover state the color is even present when we move the mouse just after the boundary.I know that this is due to StyleSheet Supporting Box approach in that case the rectangle is drawn using the different border clip property. So in this case the minimum rectangle cover the Circle
So is there any way that only color will come when the mouse is on the widget . Please answer me in terms of style sheet bcoz through Paint Event it is easy

hope for Quick reply