MDN shortlink in chapter 3 redirects to old page that 404s

[Jordy Nelson]

The link to the MDN CSS Selectors docs doesn't work in the second edition on O'Reilly:

For details on additional selectors, see the Mozilla Developer Network.

The shortlink http://mzl.la/V27Mcr has a 301 to https://developer.mozilla.org/en-US/CSS/CSS_Reference#Selectors (which no longer exists but redirects to itself).

I think the current CSS Selector docs are at: https://developer.mozilla.org/en-US/docs/Web/CSS/Reference#selectors

P.S. Thanks for making such a great resource! 🤩