It's a 386/8bit/pixel style of UI theme based on Bootstrap 3.3.7
based on original bootstrap 3.3.7 scss files, modified some variables/mixins/functions. Also some ideas are from https://github.com/kristopolous/BOOTSTRA.386, but mine is scss based, and details are different.
refer to https://getbootstrap.com/docs/3.3/getting-started/#grunt
You can use grunt/gulp to compile scss and js