WPT details: https://wpt.fyi/results/css/css-color?label=master&label=experimental&aligned&view=interop&q=label%3Ainterop-2024-relative-color There are a few subtest failures that remain with this feature in status=experimental, but those are cases for relative colors *not* based on currentcolor and are being tracked separately.
Allow relative colors in CSS (using the 'from' keyword) to use 'currentcolor' as a base. This will make it easy for web developers to set complementary colors, based on an element's text color, for that element's borders, shadows, backgrounds, etc. This feature also includes use cases where color functions are nested with a dependency on currentcolor, for example `color-mix(in srgb, rgb(from currentcolor r g b), white))` or `rgb(from rgb(from currentcolor 1 g b) b g r)`.
Relative Color Syntax was selected for Interop 2024 with a large fraction of non-passing tests covering use of currentcolor. Without this feature, web developers have to resort to sub-optimal workarounds such as passing the base color in a CSS Variable.
Docs: https://docs.google.com/document/d/1568wVjrIRbrU9_O37gPu10cj0CDWRiAc6ZMk9t0JpXs/edit