Increase Side Bar Width Using CSS

I need some help ! Here's the link to my CSS: http://thegeeksdatingguide.com/wp-content/themes/dipdolt-red-10/style.css

Now, what I need to do, is to increase the width of my sidebar, but when i do that, the width moves left, going over the content, but I need it to increase the width the other way. Can anyone point me to the right direction?

The site can be seen here: The Geeks Dating Guide

 

Your content width is set at 750px. You need to increase this if you don't want to decrease the main body content width.

 

Thanks! Got it sorted now!