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Explanation
The stepping feet illusion is a motion perception phenomenon involving two "buses," one blue and one yellow, moving horizontally across a "street" consisting of black and white stripes. Although both of the buses move at a constant speed, their perceived speed varies dramatically.
When the blue bus lies on the white stripes, the contrast is high (dark blue vs. white) and easily visible, so it appears to move faster than its actual speed.
Attributions
- The Stepping Feet Illusion on futilitycloset.com
- Stripes in CSS by Chris Coyier (css-tricks.com)
- CSS block animation jsfiddle.net
- Color palette via lospec.com