: auto; position: relative; background: red;">
  <div id="flex">
    <div style="height: 200px;"></div>
    <div style="height: 210px; margin-top: -10px; break-before: column;"></div>
  </div>
  <div style="position: absolute; height: 10px; width: 25px; top: -10px; left: 25px; background: white;"></div>
</div>
