Hi there and welcome
I wont mislead you but all signs point to the screen or system board being damaged, this is the damage you would expect when a heavy object falls on the MacBook and would result in a Blue or Green color as the LCD's are not being controlled correctly.
To be sure though it is not the NVRam or SMC I want you to do the following.
Once done, power off the Mac again
Tell me how the screen now looks please.