Block states don't seem to work with a string input, only true/false and intergers

When trying to fill with a colored block for example, I'd need to do something like ["color":black] but it never works, even trying to replace "black" with "15" but apparently that's a invalid input, this wasn't a problem before the data value thing wasn't remove, since I could do something like /fill ~40 ~ ~40 ~ ~ ~ concrete 15, but I unfortunately can't do that anymore so I now have to fill in a large area with black concrete by hand.