css/css-contain/contain-content-011.html

<!DOCTYPE html>

  <meta charset="UTF-8">

  <title>CSS Containment Test: 'contain: content' does not turn on style containment</title>

  <link rel="author" title="G&eacute;rard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
  <link rel="help" href="https://drafts.csswg.org/css-contain/#contain-property">
  <link rel="match" href="reference/contain-content-011-ref.html">

  <meta name="assert" content="'contain: content' turns on style containment. So, in this test, the counter of div.abspos child should not be reset and must not be reset.">

  <style>
  body
    {
      counter-reset: counter-of-abspos-div 17;
    }

    /*
    This creates a new counter identified as
    "counter-of-abspos-div" and initially sets
    such counter to 17 (an entirely arbitrary
    number)
    */

  div
    {
      width: 100px;
    }


  div#contain-content
    {
      background-color: red;
      contain: content;
      height: 100px;
    }

  div.abspos
    {
      background-color: green;
      height: 50px;
      position: absolute;
      right: 0;
    }

  div#contain-content > div.abspos
    {
      counter-increment: counter-of-abspos-div 4;
    }

    /*
    This increments the counter identified as
    "counter-of-abspos-div" of the step value
    of 4 (an entirely arbitrary number) each and
    every time there is a div.abspos child
    within the subtree of div#contain-content
    */

  div#first-abspos
    {
      top: 0px;
    }

  div#second-abspos
    {
      bottom: 0px;
    }

  div#result::after
    {
      content: counter(counter-of-abspos-div);
      font-size: 3em;
    }

    /*
    Now, the generated content is set to the
    current value of the counter identified
    as "counter-of-abspos-div":
    17 + 4 * 2 == 25
    */
  </style>

  <body>

  <p>Test passes if there is a filled green square, no red and the number 17.

  <div id="contain-content">
    <div id="first-abspos" class="abspos"></div>
    <div id="second-abspos" class="abspos"></div>
  </div>

  <div id="result"></div>