>Represents the length of time in milliseconds an animation or animation cycle takes to complete, such as 200 milliseconds. The type property must be set to the string “duration”. The value must be a string containing a number (either integer or floating-point) followed by an “ms” unit. A millisecond is a unit of time equal to one thousandth of a second. For example:</p>
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      <a class="self-link" href="#example-15">Example<bdi> 15</bdi><