References to CSS Counter Styles Level 3

[xfq]

I think the references to CSS Counter Styles Level 3 could be improved:

1. <a href="https://www.w3.org/TR/css-counter-styles-3/">CSS Counter Styles Level 3</a> can be changed to the ReSpec expanded reference syntax, i.e., [[[css-counter-styles-3]]]
2. After changing all the references to CSS Counter Styles Level 3 to the expanded reference syntax, we can remove the (now outdated) References section, since ReSpec will generate it automatically.