The illusion that ruined friendships since 11 years ago.
Do you still see the dress as having the same colors as you first see it, or are the colors changing to you? I always see it as black and blue, and no matter what I do, I can't have my eyeballs see it as white and gold.
Sounds like we are seeing more or less the same thing when it comes to the background.
I think the contrast provided by the strips is what makes the difference here. We don't see colour in isolation, our brain only processes colours in relation to other colours. For example, take this optical illusion:
The squares A and B are actually exactly the same colour and tone, here. If you look at each square in isolation (by eg zooming in 1000x on your screen) you'll see this clearly. It's only when the squares are put into the context of the full scene that this starts to sound counterintuitive. So we are not just processing the colour itself. We are processing the relationship that colour has to other colours.
Similarly, with the black/white + white/gold combo, I think there are probably some similarities in the relations between these two colours. If I had to guess, I'd say that when you look at the wavelength size of these colours, the black/white + white/gold combos would have the same ratios between them. Put differently: in colour space, the distance between black and blue is the same distance that white is from gold. So the relative distances between these two colours are the same even though the colours themselves are very different. That's just my best guess anyway.