<!DOCTYPE html> <html> <head> <title>CSS Variables - Animation - Substitute Into Keyframe</title> <script src="/resources/testharness.js"></script> <script src="/resources/testharnessreport.js"></script> <meta rel="author" title="Kevin Babbitt"> <meta rel="author" title="Greg Whitworth"> <link rel="author" title="Microsoft Corporation" href="http://microsoft.com" /> <link rel="help" href="http://www.w3.org/TR/css-variables-1/#syntax"> <style> @keyframes coloranim { from { color: blue; } to { color: var(--endColor); } } /* Start the animation in the paused state and fill at both ends so we can inspect values from both keyframes. */ #target { animation-name: coloranim; animation-duration: 1s; animation-play-state: paused; animation-fill-mode: both; } #target { color: red; --endColor: green; } </style> </head> <body> <div id="target">This text should animate from blue to green over a period of 1 second.</div> <script type="text/javascript"> "use strict"; // Force an initial layout pass document.documentElement.offsetHeight; test(function() { // Different browsers generate interpolated colors differently, so check multiple valid forms. assert_in_array(window.getComputedStyle(document.getElementById("target")).getPropertyValue("color").trim(), ["rgb(0, 0, 255)", "rgba(0, 0, 255, 1)"], "color is blue before animation runs"); }, "Verify color before animation"); var animationTest = async_test("Verify color after animation"); animationTest.step(function() { // Set event handler document.getElementById("target").addEventListener("animationend", animationTest.step_func(function() { assert_in_array(window.getComputedStyle(document.getElementById("target")).getPropertyValue("color").trim(), ["rgb(0, 128, 0)", "rgba(0, 128, 0, 1)"], "color is green after animation runs") animationTest.done(); })); // Trigger animation document.getElementById("target").style.animationPlayState = "running"; }); </script> </body> </html>