Hmmm, it's hard for me to say, is there a chance you can paste in an example of what you're changing? Like the menu bar stickied to the bottom, the background color is located here:

.module-navlinks {
background: #84BFC3;
bottom: 0;
color: #F1F2ED;
font-size: 0.7em;
margin: 0 auto;
position: fixed;
width: 100%;
z-index: 100;
}

And say you wanted it to be black instead of blue you would just change it to:

.module-navlinks {
background: #000;
bottom: 0;
color: #F1F2ED;
font-size: 0.7em;
margin: 0 auto;
position: fixed;
width: 100%;
z-index: 100;
}

Is that what you're doing, or?