Complex sentence: Bro-country is a subgenre of mainstream country music originating in the second decade of the 21st century that is influenced by 21st-century hip hop, hard rock and electronic music.
Split into simpler sentences: Bro-country is a subgenre of mainstream country music originating in the second decade of the 21st century. It is a general term for styles of country music taking influence from 21st-century hip hop, hard rock and electronic music.