<!doctype html>
<html lang=en>
<meta charset=utf-8>
<title>CSS-contain test: size containment on html prevents writing-mode propagation</title>
<link rel="author" title="Florian Rivoal" href="https://florian.rivoal.net">
<meta name=flags content="">
<meta name=assert content="size containment on html prevents writing-mode propagation">
<link rel="match" href="reference/contain-body-w-m-001-ref.html">
<link rel=help href="https://drafts.csswg.org/css-contain-1/#contain-property">
<style>
html::before {
content: "";
width: 100px;
height: 100px;
background: orange;
display: block;
}
p { writing-mode: horizontal-tb; margin: 0;}
body {
margin: 0;
width: 200px;
height: 200px;
writing-mode: vertical-rl;
}
html {
contain: size;
}
</style>
<p>Test passes if the orange square is in the upper-left corner.