Chromostereopsis is when colors seem to jump forward or backward because of how our eyes and brains perceive them. It happens because of the way different colors are processed in our eyes, and it can sometimes make things look like they're moving or floating!
To understand this, let's think about the colors red and blue. When you look at these colors together, they create what's called a chromatic aberration. This means that the way the colors are focused in your eyes creates a sort of blur or distortion. This distortion is what causes the effect of chromostereopsis.
So let's say you're looking at a picture with a red object and a blue object next to each other. Depending on how your brain processes the colors, one of the objects might look like it's popping out at you, while the other one looks like it's further away. This gives the picture a sort of 3D effect!
Scientists are still trying to fully understand chromostereopsis, but it's a pretty cool example of how our brains and eyes work together to create the world around us.