Hi,
we use ph-css as part of a product that uses CSS for generating print layouts. In this use case we also need to support footnotes as defined in this w3c working draft: https://www.w3.org/TR/css-gcpm-3/

However parsing CSS files that use this kind of structure, failed with ph-css:

@page {
  @footnote {
    float: bottom;
  }
}

In the grammar I added @footnote just like the other page margins even if it not a margin per se but a page area. From a CSS point of view however I think this is fine, as it does behave like a page margin.

I also added a test css file and a test, that the file is read correctly. Is test css file read by the general tests as well or is there another place to register this test file?

The other extensions from this working draft (::footnote-call and ::footnote-marker) should already work I assume. Do you see any problems with them?