Allow callers to define psuedoclasses via callback.

Drop legacy FIXME regarding media query ratios.

Add support for `@document regexp()`..

Treat ratios as fractional numbers.

I'm having trouble consulting the spec, but judging by sample CSS this looks right.

Add support for range types to media query interpretor.

This allows browsers to be more vague when fetching @imports.

Add hook for callers to run their own tests against attributes.

Add new style tree traversals.

Expand :is/:where lowering.

Codestyle: remove unnecessary parens.

Move :root handling into interpretor.

Test counters() handling against longhand rather than shorthand.

Because that's where it'll be passed

Start testing counters implementations, fix syntactic shorthand lowering for counter[s]() functions.

Release new Haskell Stylist & XML Conduit Stylist!

XML Conduit Stylist changed to abstract away Haskell Stylist's breaking datastructure changes.

Correct pseudoclass to pseudoelement rewrites to apply to only rightmost selector.

I previously got the semantics of my datastructures backwards: the head is the rightmost selector.

Remove preceding whitespace from all CSS at-rules.

Lower psuedoclasses & namespaces throughout CSS selectors.

Previously I just applied to them to the rightmost.

Rewrite parsed namespaces according to @namespace rules.

Evaluate attribute namespace selectors.

Parse namespace selectors.

Rewrite trivial cases of :where & :is.

This is mostly for the psuedoselector rewrites performed in Data.CSS.Preprocessor.PsuedoClasses