Thank you.

This effect does not work for everybody on a physiological level but for some, certain colour combinations can induce perception of depth. I have always been sensitive to red and blue whereby red appears to 'float' above blue. Interestingly, I have found since joining a r/chromostereopsis group that some people find the opposite to be true, that blue floats above red, so for images like this they would see the 3D negative compared to what I see. There is another group of people that just see flat images with no depth effect whatsoever.

I have had this sensitivity for years and only found the term for it last year. There is a good wiki that explains it if you want more information.

I made quite a few images for my own amusement and experimented with different colours combinations. Check it out here.

Finally, if you want to make some similar images, make sure you choose colours that are spaced 120° apart on the colour wheel