Auto-Coloring a Cell that Depends on the Number

Hi,

I'm looking to alter a cell's color, depending on the numerical value entered.
i.e. 1= purple 2= red, etc.

I'm aware of how to alter the conditional format to make a cell, say c15, turn purple by entering
a certain number. However, I'm not sure how to make it turn the cell the next row over that color,
since the cell I desire to change the color for will already have data contained.

Hypothetically, let's say C15 has data in it. I want to turn it purple without manually doing
it. Would a nearby cell, b15, need to have a formula to drive this coloring for c15, or rather
what's the most efficient way of doing this?



Thanks in advance for any of your help!