I've looked at the CSS default setup but it looks  totally different than the previous one. I've played around with a few settings but everything I do doesn't make a difference. Nothing changes with any settings I make.
I believe changing local css settings wouldn't make a difference. The width of the page is probably hard coded in the layout part of the css. 
Why not just resize your window, like most other people do?

Hi, my namez: "NO, Bad Kitteh, NO!"  Whaz yurs?
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