Mark "CSS-in-JS" task as done

Author: omgovich

README.md

@@ -293,4 +293,4 @@ If your port is not in the list, reach us out via [GitHub issues](https://github
 - [x] Rewrite the codebase to TypeScript
 - [x] Alpha channel support (RGBA, HSLA and HSVA color models)
 - [x] Accessibility
-- [ ] CSS-in-JS version
+- [x] CSS-in-JS version