Improve UX at the left panel

Check picture for reference:

1. Give some margin to items that are under list, folders, tags and whatever comes in the future, that helps to navigate.

2. Instead of arrows, the folders can have a FOLDER icon that can interact as open or close (icon change) when we use them, we avoid the arrows this way and is more intuitive and natural to our brain.

3. We should see the list or item that we are currently working on, 1 way to achieve this is remarking the background, this will help us to locate our selves quicly.

I have a bunch of ideas to improve the UX, I'll keep posting…