I love to make CSS do stuff it shouldn’t. It’s the type of problem-solving brain training you’d get building a calculator in Minecraft, except you probably won’t get a job working with Minecraft Redstone no matter how good you get at that, whereas CSS skills are worth actual money, and many generalist programmers are scared of CSS, so studying it can be a way to stand out from the pack. Also, when you’ve done the impossible with CSS, all normal CSS tasks seem easy.

I saw in the release notes for Safari Technical Preview 122 that it has support for a color-contrast() function in CSS. Safari is first out of the gate here.