Need for subsections!

Hi, I love the app compared to other apps of the same kind. I used to use Raindrop.io, but I prefer this app as I don’t need to open another app to consult the video. The only thing is that I would like to be able to create collection within collection or sub folders like in Raindrop.io. If I am doing a fitness collection, a recipe collection and a skincare collection well within the fitness collection itself I want to separate my core exercises from my legs, exercise exercises videos but right now it is not possible to do that as there’s no subsection option. Right now, it means that I have a bunch of collection in regards of the same things, like Fitness, mixed with collections that are completely irrelevant to that subject like recipes or skincare or whatever else.