<!DOCTYPE html>
<title>CSS aspect-ratio: img block size with box-sizing (vertical writing mode)</title>
<link rel="help" href="https://drafts.csswg.org/css-sizing-4/#aspect-ratio">
<link rel="match" href="../../reference/ref-filled-green-100px-square.xht" />
<style>
img {
  writing-mode: vertical-rl;
  border-top: 40px solid green;
}
</style>

<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>

<!--
  1st: A green rect 60x100.
       border-top is 60x40 and the content box is 60x60.
       We use 'aspect-ratio: auto && <ratio>', so the aspect-ratio works with
       content-box dimensions always. The inline size of the content box is
       (100px - 40px) = 60px, so the block size is 60px * 1/1 = 60px.

  2nd: A green rect 20x100.
       border-top is 20x40 and the content box is 20x60.

  3rd: A green rect 20x100.
       border-top is 20x40 and the content box is 20x60 because we compute
       the block size by aspect-ratio which works with border-box and so the
       block size is 100px / 5 = 20px.
-->
<img src="support/1x1-green.png" style="height: 100px; aspect-ratio: auto 1/10; box-sizing: border-box;"
><img src="support/1x1-green.png" style="height: 60px; aspect-ratio: 1/3; box-sizing: content-box;"
><img src="support/1x1-green.png" style="height: 100px; aspect-ratio: 1/5; box-sizing: border-box;">
