I'm ~1900 rapid on Lichess. As Black, I like to play this defense against
1.e4 (picked up from watching Hikaru's streams):
[FEN ""] 1.e4 g6 2.d4 Bg7 3.Nc3 c6 4.Nf3 d5 (4.f4) (4.Be3)
Are there any books or online resources available for learning more about this defense and the strategic ideas behind it?