My first #suggestion is about mobile #layout: it needs to be responsive!
And while you're there, you may want to improve the position of the two lateral columns on desktop (see screenshot) as well.
suggestion, not bug ;)
mobile comes later when base features are in place and desktop UI/UX is mostly decided (we can only do one at a time). We will make it responsive.
sidebars at the edges is on purpose. It's how youtube does it, and it gives us room for theater mode within a wide frame.