How to get space between T3-sidebar and T3-content (module) ?

Hi,

I have played with CSS but it doesn't work for me yet.

Padding, Margin, width and a bit of playing with floats didn't get the result.

I would like to create blocks where I can see backgroundpicture in between.

Any ideas?

I am building on WAMP, don't have a link at the moment to my website.