주류문화가 · 주류문화를
mainstream culture
Example
한때 비주류였던 웹툰이 이제는 주류문화가 되었습니다.
Webtoons, once on the fringe, have now become mainstream culture.
Word parts
주 main+류 stream+문 writing+화 change, -ize
Literally 'main-stream culture', just like the English image.
Good to know
Don't confuse 주류 'mainstream' with its homonym 주류 'alcoholic beverages'.