<!DOCTYPE html>
<html>
<head>
<link rel="match" href="backdrop-descendant-selector-ref.html">
<link rel="help" href="https://fullscreen.spec.whatwg.org/#new-stacking-layer">
<style>
dialog {
    visibility: hidden;
}

::backdrop {
    visibility: visible;
    position: absolute;
    height: 100px;
    width: 100px;
    background: red;
}

/* This shouldn't be matched, dialog is not the parent of ::backdrop.
 * It is given high specificity so we actually test something.
 */
#dialog-parent > #dialog > ::backd