I get your point, as I was writing it I thought "this shouldn't be too technical otherwise I end up writing a tutorial" but had to be technical enough to give some context and practical examples... But yeah, I should have gone deeper explaining the Shadow DOM part.
You can start some side projects in other language like Python or Ruby, do some coding, work on freelance gigs, and earn some experience.
That way you will have something to use in a future interview.
Great advice for time management, works well for IT positions.