Fair warning, if you load the site in dark-mode the diagrams are completely broken. They're PNGs with an alpha-transparency background and gray/black for the actual content, when the site is in dark mode you can see nothing at all...
So make sure to change to light-mode in the top-right if you want to read this article at all.
Feel like the author should have just included the white backgrounds in the PNGs.
Though the more technically fun solution would be to use SVG instead of PNG because then the author could apply a whole dark mode color palette with CSS.
(I'm the author)
Thanks for flagging! I just pushed an update that should fix this
Thank you, the selector on top right is too easy to miss.