https://drafts.csswg.org/css-color/#grays > As decided at San Francisco, this syntax is an alias to Lab with a=b=0. This was a larger issue, but was solved at the San Francisco 2016 f2f. Grays are now syntactic sugar for L=gray, a=b=0.
https://drafts.csswg.org/css-color/#grays
This was a larger issue, but was solved at the San Francisco 2016 f2f. Grays are now syntactic sugar for L=gray, a=b=0.