Atlassian is only nice for what they actually display on that page, but their design system (the components at least) is actually 2x more expansive, meaning you are out of luck if you need info on any of that.
Of course, they do give you the source, so that’s nice.
I guess mobile support isn’t part of those design systems. The Atlassian docs don’t work on mobile at all. The other two are at least functional, but look really bad.
This is the difference when you have dedicated, well-funded teams for which the design is the product. For most developers, it's something they are made to do on the side - I mean, "but you're a full stack developer, right??".
This is some of the best documentation I have ever seen, and a very elegant design, too.
WOW.
I am working on documentation for my own product right now, and this is inspiring.