background color issue

hi,

in my website my main menu have abackground color of blue. I dont need that color.but more time I change it in the style section.again it appearing.more time I try with menu background color.but it is not changing.some times changing from all other menu items except one.it still existing on the menu name on the existing page. How can it resolve.

The page I need help with: [log in to see the link]