<!doctype html>
<meta charset="utf-8">
<title>CSS Selectors Invalidation: :nth-child(... of pseudo-class)</title>
<link rel="author" title="Zach Hoffman" href="mailto:zach@zrhoffman.net">
<link rel="match" href="nth-child-of-pseudo-class-ref.html">
<link rel="help" href="https://drafts.csswg.org/selectors-4/#child-index">
<style>
  p:nth-child(odd of :defined) {
    color: green;
  }

  not-defined, my-element {
    display: block;
    margin-block: 1em;
    margin-inline: 0;
  }
</style>
<div>
  <not-defined>Ignored</not-defined>
  <not-defined>Ignored</not-defined>
  <p>Not ignored</p>
  <my-element>Selectively ignored</my-element>
  <p>Not ignored</p>
  <p>Not ignored</p>
  <p>Not ignored</p>
  <not-defined>Ignored</not-defined>
</div>
<script>
  document.documentElement.offsetTop;
  customElements.define("my-element", class MyElement extends HTMLElement{});
</script>
