There is a Halacha in Shulchan Aruch Orach Chaim Siman 529:1 that one is supposed to break up his Yom Tov into halves: Half to Hashem and half to himself. The Mishna Berura there elaborates and gives a detailed schedule as to how one should do this. He says that one should wake up and go to shul, daven, learn, Daven Mussaf, go home to eat, come back to shul and Daven Mincha.
Does staying up all night to learn on Shavuos contradict this Halacha? I ask since after Davening the next day, people go to sleep, not learning like the Mishna Berura says one should do.