No sense

Its impossible to tell you what to edit do without seeing what your site looks like and how its put together. So you’ll need to post a link to your site if you want to know what to change in your stylesheet.

To use Brush script on your site as live text you’ll need to license the webfont unless you know that everyone visiting the site already has a licensed copy of the desktop version of the font installed on their operating system (which is unlikely). You can license it at this site: http://new.myfonts.com/fonts/bitstream/brush-script/brush-script/

If you want a free alternative, you can get other webfonts for no cost (but not the one you mention) from:
http://www.google.com/webfonts or http://www.fontsquirrel.com