I can’t find it now, but I remember them saying a few years ago that they wanted to branch out more, but were having a hard time finding publishers that would back them for anything that wasn’t a walking sim.
It looks like they finally found someone willing to take a chance with them.
I used Scrimba back when they were first starting up to learn React. They aren’t actually videos - they’re recording the state of the editor, so they can say “try to do x” and you can pause and do it right there on the page without having to set anything up yourself. You can also pause anywhere and mess around with whatever the tutorial is doing.
A lot of their stuff is paid now, but it looks like they have a couple of free intro courses on HTML and CSS. I haven’t watched either of those, but I do watch Kevin Powell on YouTube and his videos there are fantastic.