This is the exact phenomenon  with the gold/white & the blue/black dress explained easily

see this figure? looks like it’s white on the bottom & grey on the top, correct?

well what if i told you they’re the exact same color?

place a finger in between where they meet.

this is known as color constancy, where the color will always remain the same, but may be altered with the various light it is constructed under. this is the exact same thing with the worldwide known dress.