css/css-animations/inheritance-pseudo-element.html

<!doctype html>
<title>@keyframes + pseudo-element inherits from the right style.</title>
<link rel="author" href="https://mozilla.org" title="Mozilla">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1757017">
<link rel="help" href="https://drafts.csswg.org/css-animations/#property-index">
<link rel="match" href="inheritance-pseudo-element-ref.html">
<style>
body {
  font-size: 30px;
}

.container {
  font-size: 5px;
  height: 40px;
}

.container::after {
  content: "";
  display: block;
  border: 2px solid blue;
  width: 1em;
  height: 1em;
}

@keyframes kf-fs5px { from, to { font-size: 5px; } }
.fs5px::after {
  animation: kf-fs5px 1s infinite;
}

@keyframes kf-fs1em { from, to { font-size: 1em; } }
.fs1em::after {
  animation: kf-fs1em 1s infinite;
}

@keyframes kf-fs100p { from, to { font-size: 100%; } }
.fs100p::after {
  animation: kf-fs100p 1s infinite;
}

@keyframes kf-fsinherit { from, to { font-size: inherit; } }
.fsinherit::after {
  animation: kf-fsinherit 1s infinite;
}
</style>
<div class="container"></div>
<div class="container fs5px"></div>
<div class="container fs1em"></div>
<div class="container fs100p"></div>
<div class="container fsinherit"></div>