2010 Masterpage Menu CSS color comes from where?

I did the crate new webproject, and was pleased to see a Site.Master page already in place. I cannot find where in the Site.css to set or change the menu’s background-color.I have added background-color: #FCFC5C; to all div.menu sections and no change? Any ideas?

The fastest way to figure out what is the style that is modifying you element is us firebug or IE developer tool. It will tell you what css or style are modifying your  element.