css/css-page/body-background-vrl-print.html

<!DOCTYPE html>
<link rel="help" href="https://drafts.csswg.org/css-page-3/">
<meta name="assert" content="Body's background is fragmented correctly in vertical-rl writing mode.">
<link rel="match" href="body-background-vrl-print-ref.html">
<style>
  :root {
    print-color-adjust: exact;
    writing-mode: vertical-rl;
  }
  body {
    margin: 0;
    background: linear-gradient(90deg, lightgray 0%, lightgray 50%, white 50%, white 100%)
  }
  @page {
    size: 800px 600px;
    margin: 0;
  }
</style>
<p style="writing-mode:horizontal-tb; position:absolute; left:20px; top:0; width:160px;">
  There should be a top-right-aligned blue box on the first page, and a
  top-aligned hotpink box on the second page.
  The background of the first page is lightgray, and the background of the
  second page is white.
</p>
<div style="width:600px; height:100px; break-inside:avoid; background:blue;"></div>
<div style="width:800px; height:100px; break-inside:avoid; background:hotpink;"></div>