String Theory Again (gone mathematical)

I’ve primarily been exploring mathematical physics these days, following a breakthrough in my understanding of classifying spaces - this opened up a lot of doors to interesting stuff like K-theory, Chern-Weil theory, Yang-Mills instantons (BPST for now, the nLab pages are fantastic) and geometric quantisation, which looks amazing so far. I’m continuing with bosonic string theory, and topological string theory also struck me as elegant, so I picked that up too - on the mathematical side of things, I’ve been learning about (very obviously string-theory inspired) orbifolds, Kahler geometry, moduli spaces and Riemann surface classification. I also wanted a more comprehensive understanding of conformal field theory than merely a single chapter from a string theory book, so I’m learning it from a dedicated book.