In 2015 Google introduced new interface which is called Material Design Lite, specially designed for websites. A year later, we see that Google is working on incorporating the Material Design language for its web version of YouTube, which you can test now.
The new visual design is not enabled by default, but you can try it by yourself if you have installed browser Chrome. The instructions come through giorgiomarinel from Reddit:
1. Go to https:www.youtube.com/?gl=US
2. Open the developer tools (ctrl + shift + i)
3. Go to the `Resources´ tab and delete the VISITOR_INFO1_LIVE cookie for the youtube domain
4. Go to the console and define the VISITOR_INFO1_LIVE cookie using the following command:
5. Reload the page