Heh. The creator writes,
9-bit colour, divvied up into 4 palettes of 15+alpha colours each, just like momma used to make. the song was made with an emulator for the Yamaha YM2612, the chip used to create the sound in the sega genesis.
Note: It’s just the intro graphics plus three minutes of song, and sadly not a deeper re-enactment of the movie in this style—though wouldn’t that be amazing?