Align Primary Links to Center

I've become more comfortable with Drupal over the past few months and have been able to figure things out on my own and by researching here. This one has me stuck.

Using Marinelli/Giordani

I want to align my primary links to center. I've used firebug to find the code in the layout.css, ( and ie6.css, and ie7.css in marinelli and giordani folders) and made the change below -

From -
#utilities #plinks {
bottom:0 !important;
left:-7px;
position:absolute;

To -
#utilities #plinks {
bottom:0px!important;
bottom:-1px;
position:absolute;
}

Making this change in firebug fixes the problem.

Here is the problem: I've edited the layout.css file and confirmed it's placement in the directory in the Marinelli theme folder, but the old code still shows up when I open the site in a browser.

I've cleared the caches via the Drupal Performance window as well as manually in mySQL. What am I missing?

The site - www.glancyhypnosis.com

Any help or opinions are welcome!