There's a spec proposal for precisely that. It's in Colour Level... 6, I believe? https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/color-contrast ht

There's a spec proposal for precisely that. It's in Colour Level... 6, I believe? https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/color-contrast https://developer.mozilla.org/en-US/docs/Web/CSS/color_value...