User blog comment:Rappy 4187/Technical Update: November 30, 2015/@comment-24473195-20151130232317/@comment-24473195-20151201152348

@Kirkburn:

Well, if you allow a custom namespace that isn't a content namespace much like MEdiaWiki newer versions. We could move all our CSS there. Personally, I dislike using content namespaces for code, but Wikia doesn't offer any reasonable alternatives aside from sticking stuff in MediaWiki:.

It also makes any link from that page appear in your insights lists. So that's yet another reason to consider this option. See []  for more info.