This new homepage is a static website generated in R (!) with the help of brilliant blogdown package by Yihui Xie. Hugo is the site engine and it also uses amazing Academic theme.
More about the blogdown R package you can find here: https://bookdown.org/yihui/blogdown/
Some additional usefull posts:
Updating website with Hugo and Blogdown
Making Site
Quick Start setting up a custom domain with GitHub pages