Found in 2 comments on Hacker News
abecedarius · 2019-01-21
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Just one suggestion, but https://www.euclidea.xyz/ is a great place to start. Visual Group Theory sounds appropriate too: https://www.amazon.com/Visual-Group-Theory-Problem-Book/dp/0...
This is targeted at the beginner. Maybe someone else can comment on how good it is. Doesn't look to be interactive, but more pictorial based.