Header Background Color Changes

Just purchased oceanic. Wanted to change the background color for the top header. I didn’t see a way to do it within the theme editor, so i used siteorigin CSS Editor.

From what i could see, it appeared as this was the area:

header.header-stick.stuck {
background-color: #cfab74;
}

With the above addition, i got what i wanted when using Chrome, but it did not work using firefox.

So, either there is a bug, or perhaps i’m using the wrong CSS.