Space between sidebar & center column?

I would like to have a home / intro page with 3 text widgets that can be clicked to lead to subsequent pages. I used the Left Sidebar, Left Inner Sidebar, and Right Inner Sidebar to create this layout. However, there seems to be a space between the left inner sidebar and the right inner sidebar, which I believe is the center column.

I did deactivate the page title and set the center column padding to 0px, but nothing changes. It would be great if somebody could help, this is my link to the site I am working on:

http://gabytobler.com/BritPat/

Thank you!!

Gaby :-)