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<html><head><style> div { width: 100px; height: 100px; background: red; position: relative; animation: mymove infinite; animation-duration: 3s;}@keyframes mymove { from {top: 0px;} to {top: 200px;}}</style></head><body><h1>The animation-duration Property</h1><p>Specify that the animation should complete one cycle in 3 seconds:</p><div></div><p><strong>Note:</strong> Always specify the animation-duration property. Otherwise the duration is 0, and the animation will not be played.</p></body></html>