So I have a div I want to change the color of when clicked. I have three divs over all and I want to denote which one is the active div when clicking on it
Basically
Make your DIVs focusable, by adding tabIndex:
Section 1 Section 2 Section 3
Then you can simple use :focus pseudo-class
:focus
div:focus { background-color:red; }
Demo: http://jsfiddle.net/mwbbcyja/