skew()

transform: skew(0);

transform: skew(15deg, 15deg);

transform: skew(-0.06turn, 18deg);

transform: skew(0.312rad);

<section id="default-example">
  <img
    class="transition-all"
    id="example-element"
    src="/shared-assets/images/examples/firefox-logo.svg"
    width="200" />
</section>

skew(ax)
skew(ax, ay)

<div>Normal</div>
<div class="skewed">Skewed</div>

body {
  margin: 20px;
}
div {
  width: 80px;
  height: 80px;
  background-color: skyblue;
}
.skewed {
  transform: skew(10deg); /* Equal to skewX(10deg) */
  background-color: pink;
}

<div>Normal</div>
<div class="skewed">Skewed</div>

body {
  margin: 20px;
}
div {
  width: 80px;
  height: 80px;
  background-color: skyblue;
}
.skewed {
  transform: skew(10deg, 10deg);
  background-color: pink;
}