css/css-multicol/multicol-span-all-004.html

<!DOCTYPE html>
<html>
  <meta charset="utf-8">
  <title>CSS Multi-column Layout Test: column-span:all should act like column-span:none in different block formatting context</title>
  <link rel="author" title="Ting-Yu Lin" href="mailto:tlin@mozilla.com">
  <link rel="author" title="Mozilla" href="http://www.mozilla.org/">
  <link rel="help" href="https://drafts.csswg.org/css-multicol-1/#column-span">
  <link rel="match" href="multicol-span-all-004-ref.html">
  <meta name="assert" content="This test checks a column-span:all element should act like column-span: none if it's under different block formatting context.">

  <style>
  #column {
    column-count: 3;
    column-rule: 6px solid;
    width: 500px;
    outline: 1px solid black;
  }
  h3 {
    column-span: all;
    outline: 1px solid blue;
  }
  </style>

  <body>
    <article id="column">
      <div>block1</div>
      <div style="display: inline-block;">
        <h3>non-spanner</h3>
      </div>
      <div style="overflow: hidden;">
        <h3>non-spanner</h3>
      </div>
      <table>
        <caption>
          <h3>non-spanner in caption</h3>
        </caption>
      </table>
      <div style="display: grid;">
        <div>
          <h3>non-spanner in grid</h3>
        </div>
      </div>
      <div style="display: flex;">
        <div>
          <h3>non-spanner in flex</h3>
        </div>
      </div>
      <div style="column-span: all; outline: 1px solid green;">
        Spanner
        <h3>non-spanner in a spanner</h3>
      </div>
      <div>block2</div>
    </article>
  </body>
</html>