"Mastery" is probably a little exaggerated. This is more my path beyond jQuery.
- You Don't Know JS (ditto; series)
- https://frontendmasters.com/ (so many video-based courses on intermediate to advanced topics; worth subscribing if possible)
- https://www.codecademy.com (more basic, but also more interactive)
- http://teamtreehouse.com (ditto)
- https://codefights.com/ (fun and short "fights" or races to squash bugs)