Nav Bar
 

Hello, bit stuck as usual.

Code:
#channel-tabbar {
background: url("images/css/sprite_gradients_vb.png") repeat-x scroll 0 -50px #033145;
border-bottom: 1px solid #C4C7C8;
height: 35px;
text-transform: uppercase;
width: 100%;
Why can't I edit this anymore?

Thank you a.

- - - Updated - - -

I check the changes with Firebug but cannot affect the global.css.