Kanizsa Square

Open fullscreen view :root::before { aspect-ratio: 1; background: radial-gradient(farthest-side circle, #0000 80%, #fff 0) 0 0, conic-gradient(from 180deg, #000 75%, #0000 0) 0 0 no-repeat, conic-gradient(from 270deg, #000 75%, #0000 0) 100% 0 no-repeat, conic-gradient(from 90deg, #000 75%, #0000 0) 0 100% no-repeat, conic-gradient(from 0deg, #000 75%, #0000 0) 100% 100% no-repeat; background-size: 50% 50%; content: ""; left: 50%; margin: 0; position: absolute; width: 60vmin; top: 50%; translate: -50% -50%; /* hack to remove background line */ mask: conic-gradient(#000 0 0) 50% 50% / 99% 99% no-repeat; }

About This Illusion

When people look at this illustration, they usually say they see a white square over black circles. However, the square is not actually there. The "Pac-Man" shapes create the illusion of a square and a sense of depth. Our brain fills in the missing information.

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