Graceful regression

[MattMcAdams]

I want to make sure these styles degrade in a way that still provides a functional experience to users with older tech like IE. Normally, this isn't something I'd fret over for a small project like this, but I am using a lot of newer features and want to cover my bases. To be clear, I'm not supporting old text 1:1, there will be some visual regression, I just want to make sure everything is still legible and accessible.

This might involved some supports queries and/or some fallback properties, but I don't intend to do large polyfills or add something to the build script.