Help with Formula for Colorization

I have this formula and wanted to add a second field called Status if it equals "Open" as a parameter. I've tried lots of different things but I know I'm just missing something easy.

Case(true, [Due Date Calculation]=0,"#FF8040", [Due Date Calculation]>0,"#FF5050", [Due Date Calculation]=-1,"#FFFF00", [Due Date Calculation]=-2,"#FFFF00", [Due Date Calculation]=-3,"#FFFF00")

The above formula works but if the status is closed, it still highlights so I only want the Open tasks to be colored. Any help is appreciated.