Make a sphere rotate the opposite direction a player is looking in VR

Hi I have a static camera attached to a player. The player is inside a sphere playing a 360 video. I would like the sphere to rotate the opposite direction the camera is looking, so when viewing on cardboard if you look one direction the video will move the opposite. I am a beginner and have no idea where to start. I have been googling for hours and cant figure it out. Thanks!

In Unity, all rotations are handled through Quaternions. So, what you probably want is the Quaternion.Inverse() function.

Unfortunately, I am not sure about the code to take the movements from the head and translate them onto the sphere? Then maybe I can use the Quaternion.Inverse() function.
Thanks for your answer @FortisVenaliter .