How to keep layout left-aligned?

Hi, I'm revisiting this topic because I've now understood what the problem really is. I originally thought it was about defining absolute widths for each module, but I can see that everything is relative in the template set-up.

I want to keep the left module left-aligned in a window so that I can put a vertical menu there - without it changing position if the website visitor increases the size of the window.

(see original layout in image no. 1)

I see that if the browser window is widened then the whole layout is centered in the window. This means that there's a huge white gap on the left of the window before the text (or in my case the menu) is displayed.

(see image no. 2)

How do I alter the template so that everything stays left?

(see image no. 3)

What is the link to site?