Here is the Gradient Placer. This is the same as Elyrio3's, but with a small correction to work in versions higher than 1.21. Specifically, I set a gradient degree of 9 for a height of 180 blocks starting from layer -63 to 117. The gradient is spectacular, this model is useful for making an exact 3-color design.

The explanation of how to use it is in this video (Gradient Placer) at exactly 19:18. You can use Brave to have the video translated to Spanish because the original is in English.

NOTE: Do not rotate the schematic, leave it as it is

All credits to: Elyrio3.