you too? = 너 도? Pronunciation: "no doh" (pronounced like "dough")

Informally (with friends), it'd be "neo (nuh) do" 너도, otherwise you might use titles (like "eonni do" 언니도 (big sis too), etc.). It makes me think that there are a lot of situations when you can just reply "You too" in English, but it seems to me that most cases would be unnatural in Korean.