It's an OKLCH color picker, as well as a converter for other color spaces.

https://cmringmaker.github.io/OKLCH-Picker/

https://github.com/cmRingmaker/OKLCH-Picker/

I was inspired by the article over at evilmartians[0] about OKLCH, and I loved their oklch picker. Decided I wanted to learn more about OKLCH by implementing my own tool that I've released this week. Had a lot of fun with this project, and am getting plenty of usage out of it already.

[0] https://evilmartians.com/chronicles/oklch-in-css-why-quit-rg...