Logosize in header / header size

Hi Greg,

first of all thank you for that brilliant theme. I love it.

I have a litte question though: When I make use of the logo option and add it to the header the gap to the top and bottom of the logo is quite big. I mean that there is about one centimeter of blank space above and under the logo. Can you tell me how to reduce the size height of the header so that it will just about as high as the logo is ?

Thank you many times in advance

Joe