<!DOCTYPE html> <meta charset="utf-8"> <title>CSS Animations Test: animation-timing-function - step-start</title> <link rel="author" title="Intel" href="http://www.intel.com"> <link rel="reviewer" title="Zhiqiang Zhang" href="mailto:zhiqiang.zhang@intel.com"> <!-- 2015-05-07 --> <link rel="help" href="https://drafts.csswg.org/css-animations-1/#animation-name"> <link rel="help" href="https://drafts.csswg.org/css-animations-1/#animation-duration"> <link rel="help" href="https://drafts.csswg.org/css-animations-1/#animation-fill-mode"> <link rel="help" href="https://drafts.csswg.org/css-animations-1/#animation-timing-function"> <meta name="flags" content="animated"> <meta name="assert" content="When animation-timing-function is set to step-start, animation will play the end effect at the start of the interval."> <style> div { height: 100px; width: 100px; position: absolute; } #test-step-start { animation-name: sample; animation-duration: 10s; animation-fill-mode: forwards; animation-timing-function: step-start; background-color: blue; } #ref-no-animation { background-color: red; left: 150px; } @keyframes sample { from { left: 0px; } to { left: 150px; } } </style> <body> <p> Test passes if there is a filled blue square with 'Filler Text', which stays right, and if there is NO red. </p> <div id="ref-no-animation"></div> <div id="test-step-start">Filler Text</div> </body>