Cocoon skin, flush left

[rant boss]

I'm using the cocoon skin, having great success, but have a couple things I can't figure out.

First, how can I adust the skin so that the content stays flush left (in other words, all the elements center in the screen no matter how wide the broswer window...I would like to eliminate the margin on the left and have all centent stay flush left no matter how wide the browser window is opened.

What css(?) file do I open, and specifically what code do I have to change?

Thanks in advance for your reply