Okay, so what you need to do is use the second column from worksheet one to define the offset for the vlookup. That's do-able.

First, in worksheet 2, insert a row right under the numeric values. In that row, enter the number 1 in column A, 2 in column B, 3 in column C, etc. That's what you'll use to determine the offset for the vlookup and you'll use an hlookup to do it. Now, worksheet 2 looks like this:

and worksheet 1 looks like this:

With this setup, you can use an hlookup formula to look up the value in the second column (11) and return the number directly below that value (2) in the lookup table (which is exactly the number you need for the third argument in the vlookup formula). And your vlookup formula can use the value from the first column in worksheet 1 (1) and the offset you just determined (2) to return the correct color (green).

Just make sure the lookup table you use in the hlookup formula is the area outlined in red and the table you use for the vlookup formula is the area outlined in blue.