CSS ordering causing cascade issues

[aalin]

:css
  .paragraph { margin: 1em 0; }
%p.paragraph
  %slot

:ruby
  Paragraph = import("./Paragraph")
:css
  .override { margin: 0; }
%Paragraph.override
  It is possible that this override doesn't get applied because
  the stylesheets were loaded in the wrong order.

I don't know it it would be possible to solve this somehow with @layer. Maybe could get the order from the dependency graph and insert the order into the root css file...

[aalin]

Would probably be fixed by #61