Edit gkbg to include repeating image?

I think gkbg is where the change should occur but I just can't seem to figure out where it is in CSS or... if it's somewhere else?

I want to repeat a small image in the page background (not the wrapper, of course) in ver. 2.4 Financial Business.

Our current site is here and it's that blue-on-blue diagonal stripe that we want to repeat:
http://www.okwondertorium.org

Can anyone advise?... location and code?

Thank you in advance!

I have just checked your website and it seems you have found your solution, let us know if you still need further help on this.

See you around...