Copying Cell Background with Formula

[Dynamo418]

NBVC will cringe at this, but I have another question.

I have a column which is divided into 5 different color groups, their sizes depending on user input.

I now need 3 adjacent columns to have the same cell color backgrounds, and to be updated alongside the original column when the user updates the group sizes.

This seems fairly easy, but I'm not entirely sure where to begin. I don't think conditional formatting would be very helpful, perhaps this is more of a VBA question?

Cheers,

Simon

EDIT: I have attached a sample of the final product, no code involved.