This site is build on Astro and is originally based on the Astro-Sphere theme by Mark Horn.
It’s actually been quite a while since I last rebuilt this, my “Instructor’s Website. The previous incarnation (6 years ago) was based on VuePress (which, incidentally, just went to a 1.0 status!). It seemed my best choice at the time, and before that I think it was done in Angular 1.x.