White's Illusion

Open fullscreen view :root { height: 100vh; background: repeating-linear-gradient(#fff 0 8.3333vh, #000 0 16.6666vh); display: flex; justify-content: space-evenly; &::before, &::after { content: ""; width: 20vw; background: #888; mix-blend-mode: darken; } &::after { mix-blend-mode: lighten; } }

About This Illusion

These two gray columns in a black-and-white grid are the same shade of gray, but the one surrounded by black appears darker than the one surrounded by white.

I coded this demo using mix-blend-mode so I could try something a bit different. That worked well, but it also made it harder to showcase the effect on hover. In hindsight, I should have planned that better.

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