JR East South Hokkaido pass

Hi,

I wish to visit Hokkaido from Tokyo.
Pls advise if there is any mid night train operating from Tokyo to Sapporo.
Pls advise do we need to transit to other train for journey from Tokyo to Sapporo.
If there is no mid night train, what is the earliest train from Tokyo to Sapporo. Which is the nearest station from Hamamatsucho station, Tokyo.
How many total hours will take from Tokyo to Sapporo.

Pls advise also on the return train schedule if available.
Wondering any interesting spot that we can stop by along the JR journey from Tokyo to Sapporo.

Thank you very much!