<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">

 <head>

  <title>CSS Writing Modes Test: 'vertical-lr' and margin collapsing - elements with 'overflow' set to 'hidden'</title>

  <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/" />
  <link rel="help" href="http://www.w3.org/TR/css-writing-modes-3/#logical-direction-layout" title="7.4 Flow-Relative Mappings" />
  <link rel="match" href="../reference/ref-filled-green-100px-square.xht" />

  <!--
  Test adapted and modified from
  http://test.csswg.org/suites/css2.1/nightly-unstable/html4/margin-collapse-009.htm

  "
  The margin collapsing rules apply exactly with the block-start margin substituted for the top margin and the block-end margin substituted for the bottom margin.
  "
  -->

  <meta content="ahem image" name="flags" />
  <meta name="assert" content="This test checks that elements with 'overflow' set to 'hidden' do not collapse margin with in-flow children in 'vertical-lr' writing-mode. In this test, we are testing and checking that 'margin-left' of div#overflow does not collapse with 'margin-left' of div#nested." />

  <link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
  <style type="text/css"><![CDATA[
  div
    {
      font: 25px/1em Ahem;
      height: 4em;
    }

  div#wrapper
    {
      background-color: green;
      width: 8em;
      writing-mode: vertical-lr;
    }

  div#overflow
    {
      background-color: white;
      margin-left: 4em; /* block-start margin of overflowed block */
      overflow: hidden;
      width: 4em;
    }

  div#nested
    {
      background-color: red;
      margin-left: 4em; /* block-start margin of sub-block */
      width: 4em;
    }
  ]]></style>

 </head>

 <body>

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

  <div id="wrapper">
    <div id="overflow">
      <div id="nested"></div>
    </div>
  </div>

 </body>
</html>