YouTube turned 12 this week and is marking the milestone with a redesign of its desktop site. Video platform YouTube is opening up a preview of its new Material Design desktop site to a small group of people. The new design, taking advantage of Google’s Material Design language, makes the site cleaner, simpler and more consistent with YouTube’s mobile app. Brian Marquardt, product manager, explained that the site design is built on a faster framework named Polymer, which enables quicker feature development. New dark theme arrives on YouTube“We are introducing one of the first new features developed on Polymer: Dark Theme.