y must be set to the string “cubic-bezier”. The value must be an array containing four numbers. These numbers represent two points (P1, P2) with one x coordinate and one y coordinate each [P1x, P1y, P2x, P2y]. The y coordinates of P1 and P2 can be any real number in the range [-∞, ∞], but the x coordinates are restricted to the range [0, 1]. For example:</p>
  <aside class="example" id="example-16"><div class="marker">
      <a class="self-link" href="#example-16">Example<bdi> 16</bdi></a>
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