I've developed a handy tool for Visual Studio Code that makes checking CSS compatibility very easy for developers.
It provides instant feedback on syntax, keywords, types, and function compatibility. It even highlights deprecated, non-standard, and experimental features.
It looks like it's pulling from the MDN docs for the dataset (the grid and language are identical.) In this case, it's not going to be up to date, because MDN has fallen behind. For example, MDN still lists container style queries as unsupported by Safari, but Safari has supported them for three months.
