<!DOCTYPE html> <html> <meta charset="utf-8"> <title>CSS-Writing Modes Test: propagation of the writing-mode property from body to root</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-writing-modes-3/#principal-flow"> <link rel="match" href="wm-propagation-body-dynamic-change-002-ref.html"> <meta name=assert content="The writing mode of the newly inserted body must be propagated to the root."> <script> function runTest() { document.body.offsetHeight; var newBody = document.createElement("body"); newBody.id = "new-body"; var oldBody = document.getElementById("old-body"); /* Insert a new <body> before the old one, which should become the primary <body>. */ document.documentElement.insertBefore(newBody, oldBody); } </script> <style> #new-body { /* This writing-mode should propagate to the root element. */ writing-mode: vertical-rl; margin: 0; } #old-body { writing-mode: horizontal-tb; inline-size: 100px; } div { background-color: blue; height: 100px; width: 100px; } </style> <body id="old-body" onload="runTest();"> <div></div> <p>Test passes if you see a blue square in the upper-right corner of the page</p> </body> </html>