All of the MaxWiki sites use hierarchical stylesheets. Here are the stylesheets that She's Geeky uses:
1. http://shesgeeky.org/stylesheets/main.css
2. http://shesgeeky.org/themes/camp/stylesheets/theme.css
3. http://shesgeeky.org/files/shesgeeky/site.css
Stylesheet 1 is used by all MaxWiki sites. #2 is used for all sites that have the "camp" theme. And #3 is used for specific She's Geeky formatting. So if you want to change the look and feel of just She's Geeky, then you would put your changes in #3. However, you will still have to reference #1 and #2 because you may need to override some of the styles in those sheets. However, don't put more in #3 than you have to, because at various times we will make changes to #1 and #2 and those need to propagate down to the individual sites.
If you are technical, The best way to make these changes is to install MaxWiki on your local computer, which entails installing Ruby, Rails, MySQL and getting the MaxWiki code through SVN.
Another options is to grab a few HTML pages and the stylesheets onto your local drive and change the stylesheets hrefs in the HTML to point to your local copies. Then you can make all the changes and send them to me when done. Note that you can only change the CSS, HTML changes for the template are done in the MaxWiki code.