Conditional formatting moves with autofilter

[SeanWills]

Good afternoon,

I have a spread sheet where I am looking at using a traffic light system dependant on the value of the cell.

I have 3 different thresholds for 3 different sizes:

Small:
in-between 1 - 4 (Green)
in-between 5 - 12 (Yellow)
greater than 13 (Red)

Medium:
in-between 1 - 8 (Green)
in-between 9 - 16 (Yellow)
greater than 17 (Red)

Large:
in-between 1 - 10 (Green)
in-between 11 - 20 (Yellow)
greater than 21 (Red)

I already have a formula in the cells which i want to apply the colour change to. So i used conditional formatting, however, when i applied the different thresholds it worked fine but when i use the auto filter the conditional formatting stays with the row and does not move with the appropriate cell value (For example a large premise moves into a small premise cell and the threshold colours do not match).

So what I am struggling to do is write a formula that i can use for one rule to make the cell green which basically did the following:

If column A contains the word "Large" then apply (>=1 and <=10) to the cell, but if column A contains the word "medium" then apply (>=1 and <=8) to the cell, but if column A contains the word "small" then apply (>=1 and <=4) to the cell,"true","False".

Know that sounds confusing and hope someone can help me, if not through that way, another (maybe easier) way to get the conditional formatting to stick with the cells when they move.

PLEASE I NEED HELP!