It works for me on Firefox on Android. The color wheel thing is sticky while the rest of the content is not. The wheel changes to illustrate each new example as they're scrolled past.

To be clear, it’s still a super neat project.

The drilling feels smoother than I remember, but I could be misremembering.

It might help to put some sort of solid or mildly transparent background behind the color wheel so that when content scrolls up it appears to disappear behind the color wheel instead of being right there behind it competing with it visually.