On many websites selling (or offering) a software, there is an almost constant desygn style. I think of (among many others) atom.io, angularjs.org, nodejs.org, typescriptlang.org, v-play.net, qt.io and code.visualstudio.com.
They all have a header which is always on top of the screen, a black footer, and white body and often paragrpahs with a picture alternating left floating and right floating.
Is it only the 2010's fashion, or are all of these powered by a specific CMS/framework/something ?