picture between categories

Hi,

I would like to have, between categories in the forum, background picture, like this:

You mean you want to have the categories in tabels, instead of attached to each other?

Try ACP -> Display -> Structures and hierarcy -> Split categories on index: Medium.

I know that. How to set picture in place between categories.

EDIT: I'm do that, but now i have one more problem.
editor must be white, but it is black, how I can fix that?