Tokyo-Yokohama on NYE for fireworks?

Hey there! I'll be spending the holidays in Japan this year and would love to see a display of fireworks on NYE. I've heard the one at the port in Yokohama is quite something. I'm a little concerned about transportation to and from Tokyo since I'll be staying at a hotel there, especially considering it's NYE. Are there trains that run on that day? I'm assuming it'll be fine to get there, the trip back after the fireworks has got me slightly worried. Any help/advice is appreciated, thanks!