Margin Help

I customized my own layout from the default theme. I can’t for the life of me figure out how to get rid of the margin between the navigation bar (div name nave) and the content below (all three column divs in a wrapper div called main.

Anny suggestions?

http://www.becksterslaboratory.com/blog

Also, when I go to a page (see About), the footer follows the content and overlaps the sidebar. Isn’t the wrapper supposed to prevent this.

I know I already posted this, but when I tried to reply to add the last bit, it says the topic has been closed. I don’t know why this is. I’m not posting a theme, so I don’t need to post the license. I don’t know what it is! What am i doing wrong?