chromium/third_party/blink/web_tests/wpt_internal/printing/page-fitting-002-print-ref.html

<!DOCTYPE html>
<script>
  if (window.testRunner) {
    testRunner.setShouldCenterAndShrinkToFitPaper(false);
  }
</script>
<style>
  @page {
    size: 400px 300px;
    margin: 0;
  }
  @page different {
    size: 300px 400px;
  }
  body {
    margin: 0;
  }
  .page {
    display: flex;
    overflow: clip;
  }
  .page > div {
    margin: auto;
    background: yellow;
  }
</style>
<div class="page" style="height:300px;">
  <div style="width:360px; height:260px;">
    Default size.
  </div>
</div>
<div style="page:different;">
  <div class="page" style="height:400px;">
    <!-- Margins are also downscaled. -->
    <div style="width:268px; height:368px;">
      <div style="scale:0.80; transform-origin:top left; width:125%;">
        Scaled down, and in portrait mode.
      </div>
    </div>
  </div>
</div>