Widget slider to control light

I seem to have this all working, apart from one thing - the slider that controls the light temperature. So basically it’s a color slider that will graduate between two pre-defined colors. I have tried using two vector parameters and flip-flopping them, which will give me the color change in a very binary way, but I need the slider to graduate and represent all of the colors in between. Does that make sense? Is there an easy way to do this? I really appreciate your help @everynone