Підтримати Sievers Study Hall

I've created a webapp to practice key competencies in German, especially in Grammar and Conjugation:

https://www.sieversstudyhall.com/

It is designed to do the unsexy but necessary work required to learn a language by focusing on one skill at a time. The user interface is minimalist and the webapp can be used on desktop and mobile.

I want this webapp to be as useful as possible, so feel free to reach out if you have any idea to improve it :)