According to the communist manifesto, what would finally happen to the bourgeoisie?

Marxism came from the the writing of Karl Marx and Friedrich Engles. They wrote the communist manifesto and Das Kapital, the ideas mentioned in these books came to be known as Marxism. According to Marx and Engles the common workers were proletariat and those who held power in the society were bourgeoisie, the society was always divided into classes and the bourgeoisie has always exploited the proletariat. The struggle between bourgeoisie and proletariat has been going on in all of history. They both believed that  in a perfect world these classes wont't exist and bourgeoisie would disappear.