This project takes a list of color vales extracted from WordPress 5.5, and matches those colors against a given palette of brand colors. The distance between each color is measured, and the color is matched to the closest brand color. If a given color is too "far away" from any palette color, it's set aside, and all unmatched colors are shown at the end of the page.
This uses the Lab color space to calculate color difference. I found this method (CIE76) worked better than distance in RGB, while still being simple enough to implement in JS.
For more information on the colors used, check out the docs for colors.