Hiding the main logo(on pages other than the front page)

Greetings.

I am working on reducing the data usage of our forum(for mobile users), and came to the conclusion that hiding the main forum logo on all but the main page would help that(and it is not all that important to see it everywhere anyway). In case it is not clear, i mean the image on the top of the forum.(in our case, the space image.)

Is there some function in the admin panel that i did not notice? Or can this only be done with javascript that i know nothing of?

Forum: http://warhammerrejects.forumc.net/

Thanks in advance