Design changes are a-coming!
(Okay, design changes have a-come.)
If you're wondering what happened here, the short of it is that the site's design has been updated to use the Codidact design framework, which will make the eventual switch to the Codidact platform a little easier to cope with.
The long version is this. The software running this site hasn't changed - as mentioned back at the start, Writing is still running on temporary Q&A software while we wait for the full Codidact platform to be developed, at which point the site will switch over to using that instead.
When Codidact is finished, it'll use a design framework that we've developed for it called Co-Design. The changes here today have switch Writing over from using a custom design based on the original QPixel design (which, hey, it worked, but it wasn't wonderful) to also using Co-Design. One of the big things this means is that when the Big Switchover eventually comes, the look and feel of the site will be similar - not everything will be in the same place and there will be some conceptual differences, but having a single common theme will help to make the changes less onerous.
That's not to say that there are no problems with this new design: I'm sure there will be. We've ironed out a bunch of the big problems while we put this design in place, but if you notice anything wrong or that could be made better in some way, please drop an answer on this question and we'll try to smooth things out.