css/css-transforms/3dtransform-and-position-sticky-002.html

<!DOCTYPE HTML>
<title>CSS Test (Transforms): position:sticky on an element in a preserve-3d scene</title>
<link rel="author" title="L. David Baron" href="https://dbaron.org/">
<link rel="author" title="Google" href="http://www.google.com/">
<link rel="help" href="https://www.w3.org/TR/css-transforms-2/#3d-transform-rendering">
<link rel="help" href="https://www.w3.org/TR/css-position-3/#stickypos-insets">
<meta name="assert" content="3D scene intersection is done correctly in the presence of position: sticky.">
<link rel="match" href="3dtransform-and-position-sticky-ref.html">

<style>

div, img {
  height: 100px;
  width: 100px;
}

#outer {
  transform-style: preserve-3d;
  perspective: 300px;
}

#middle {
  transform-style: preserve-3d;
  position: relative;
}

#inner1 {
  background: aqua;
  /* isn't really sticky because of the containing block established by transform and by transform-style */
  position: sticky;
  top: 0;
  transform: translateZ(0);
  transform-style: preserve-3d;
}

#inner2 {
  background: olive;
  position: absolute;
  top: 0;
  left: 0;
  transform: rotateX(30deg);
}

</style>

<div id="outer">
  <div id="middle">
    <div id="inner1">
    </div>
    <div id="inner2">
    </div>
  </div>
</div>