Increase logo size in Headline theme

I am trying to increase the logo size in the Headline theme. Is there a way to do this via code injection, or does it require a CSS change? If it’s CSS, what is the correct CSS file and code change that needs to be made? Thank you.

Something like this:

.gh-head-logo img {
    max-height: 100px!important;

This worked, thank you very much @Cathy_Sarisky. How would I add about 20px of padding on top of and below the logo?

The short and untested answer would be to adjust padding-top (or margin-top) and -bottom.

The slightly longer answer would be to right click on the logo, choose inspect (in either firefox or chrome at least) and see what the current settings for those values on the elements are. (You can actually adjust them temporarily to see what effect you’ll have by doing the code injection, too.)