How to set a FIXED body margin?

[silurius]

How do I set a left-hand margin that cannot be penetrated by any forum content whatsoever?

I got design specs that were extremely specific about setting the distance from the top- and left-hand margins, and I'm pulling my hair out for the left. Under certain resolutions, or when I stretch the page by hand, the forum content enters the space on the left, no matter what steps I take.

Editing the margins and margin widths in Main CSS do have influence on it, but this does not prevent the forum content from encroaching on the left-hand margin as illustrated in the second illustration above. What am I missing?

Body extra CSS (played with variants of this):

margin: 5px 2px 2px 20px;
margin-top: 150px;
margin-left: 20px;
padding: 2px;

The interesting thing is that when I manually stretch my browser vertically (or resize my display), it does not encroach on the top margin, only when I stretch the browser horizontally (or view in dif. resolution).

I've also set percentage and pixel defs in StyleVar, added tables and spacers to header & footer & forumhome, to no avail; stretching the browser page still allows forum content to move and enter a background image that occupies the top-left of my page.

How can I set it so that the left-hand space is completely safe?

[silurius]

Well, I spent some time and as of now I've addressed the problem in Firefox/Opera browsers only. At this time, I do not know of a way to get around this for IE.

The following CSS element in Main CSS -> Body will lock that left-hand margin space down for Firefox/Opera browsers:

min-width: 1100px;

There may be other tricks of which I am not yet aware. Please post here and PM me if you happen to know of a better solution!