Change default header menu background color

Hello, the default header menu background color and I want to change it to some other color. I know I could use the theme’s panel, but when the site loads up, the default color loads first and after that the one I set loads, and it looks awful.
I want to change the base color for the menu from the theme files, how can i do that ? Thanks.

Hi

You can make the modification directly in style.css file: http://screencast.com/t/2Op3GpJuWYgB

Thanks!