Family Tree theme help

Hi,

We have just set up the Genesis Framework Family tree theme on http://www.bmgcinema.co.za . The problem we are having is that the logo image needs to be 960x230px. We have set the image to that size, but it still gets cut off at the bottom of the logo.

I have tried to change the styles.css, but that does not seem to have any effect. Can someone give me some advice on what I need to change to make sure that the bottom of our logo does not get cut off?

Thanks so much.

Regards

Kim