[Forums] CSS and Javascript

Hi guys,

I'm having some troubles integrating CSS code with Javascript functions.

I'm trying to draw a plain checkbox with gray borders, when not checked. When the user checks it, I want the box to become blue, as well as the check icon.  (Something like this)
Am I wrong in concluding that the only way to do this is by comunication between the CSS and JavaScript? Is it possible to do?

Thanks for any help.