Fill a histogram with different colors for different fit functions

Hi, I have a histogram on which I have fitted two functions (one for bkg, the other is bkg+signal) as attached. I would like to fill the histogram with a different colour under the background fit function (the red line here). How could I possibly do so?

ROOT Version: 6.24/02

If your fit function is f1, you can try something like


check out the fill styles in the TAttFill docs.