i want to use the =if function to apply a colour to other cells

[pookie1970]

basically i want o be able to change the cell colour of other cells depending
on a numbered code.

for example cell A1 has '1' then colour all cells b1..z1 in 'red'

I want to be able to apply this to other numbers and use other colours.

any ideas?? I have tried conditional formatting but that relates to a
specific cell value.

 

[bj]

in conditional formating, use formula is rather than value is.