Changing header size in Businessup theme

Can someone steer me to the code that sets the header and help me reduce the height and the font sizes? It is much too tall for my use and the fonts too large. This code is apparently in the CSS somewhere but I have been unable to find it.

I am referring to the large block that contains an image and also a menu, apparently. The block rolls up and down transprently as you scroll, causing different prortions of the background behind it to appear. I really don’t need this feature either.

Thanks