Changing background color

Hi,

I’m new to this forum, and also to this theme. I’d like to change the background color of the slider on the home page and every page where i use this slider. I’d like to change it to one color, that every page have the same color.

I red all topics on this forum that may have the solution to my problem, and i’ve tried them all. Some one an idea, what i can do to change de background color?