Polyfill for @supports is https://github.com/kjarmicki/fq-polyfill and for CSS.supports() is https://gist.github.com/codler/03a0995195aa2859465f
Polyfill for @supports is https://github.com/kjarmicki/fq-polyfill
and for CSS.supports() is https://gist.github.com/codler/03a0995195aa2859465f