Sailor Moon Pink Tint - Depending on what you use to play NES games, its colors will be different.

To be more specific, the NES/Famicom outputs its visuals as an NTSC video signal, which is then decoded by the TV. Different TVs handle this differently, which is why NES colors can change so much from setup to setup. In that case, the closest we can get to an "original intention" is mimicking the displays that developers used to make and playtest games.

Other systems display colors by assigning them to pure RGB values, which is why you don't see this with, say, SNES games.

I actually have an rgb modded nes that has a switch that can change color pallets.