How can I use conditional formatting to set a cells colour equal to another cells colour?

I'm trying to organize some numbers (related to character experience use in a tabletop RPG), and I would like to be able to colour one cell by just copying the colour of the cell to its immediate right. Effectively, I would like conditional formatting that says something like "B1.Colour = C1.Colour", but I can't seem to find any documentation supporting this.

Is this possible? If no, is there another simple way to do it?