For being a site about design, I absolutely hate the monospace font they've chosen here; it really wrecks the design as a whole and disrupts the clean and simple paradigms MD shoots for. I love material design (and use it in the majority of my products e.g. [1]), but their existing docs[2] look so much better than this new site.

[1] http://www.notebook.ai/ [2] https://material.google.com/