<!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 Multi-column Layout Test: nested multicolumns and vertical margin (complex)</title>
<link rel="author" title="Opera Software ASA" href="http://www.opera.com/" />
<link rel="reviewer" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/" /> <!-- 2013-08-14 -->
<link rel="help" href="http://www.w3.org/TR/css3-multicol/#the-multi-column-model" title="2. The multi-column model" />
<link rel="match" href="multicol-nested-margin-002-ref.xht" />
<meta name="flags" content="ahem" />
<meta name="assert" content="This test checks that when an inner nested multi-column element is preceded by a soft column break (caused by an unforced column-break), then the used margin-top of such inner nested multi-column element is '0'." />
<!--
More info:
Re: [css3-multicol] vertical margins rendering in nested multi-columns
http://lists.w3.org/Archives/Public/www-style/2013Aug/0146.html
-->
<link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
<style type="text/css"><![CDATA[
body {margin: 0;}
body > div
{
background-color: yellow;
font: 1.25em/1 Ahem;
width: 41em;
/*
This test requires a viewport width of 820px
*/
}
div
{
color: yellow;
font: inherit;
orphans: 1;
widows: 1;
column-count: 3;
column-gap: 1em;
}
div div {margin: 0em 1em;}
div div:last-child
{
color: blue;
margin: 1em;
}
/*
N == 3;
W == max(0, (available-width - ((N - 1) * column-gap)) / N);
W == max(0, (41em - ((3 - 1) * 1em)) / 3);
W == max(0, (41em - (2 * 1em)) / 3);
W == max(0, (41em - 2em) / 3);
W == max(0, 39em / 3);
W == max(0, 13em);
W == 13em;
The height of column rule depends on number of line boxes in
each outer column box which depends on number of line boxes
in each inner column box. So:
13em : width of each outer column box
-
2em : horizontal margin of each div inside
=======
11em : width of each inner multi-column elements
N == 3;
W == max(0, (available-width - ((N - 1) * column-gap)) / N);
W == max(0, (11em - ((3 - 1) * 1em)) / 3);
W == max(0, (11em - (2 * 1em)) / 3);
W == max(0, (11em - 2em) / 3);
W == max(0, 9em / 3);
W == max(0, 3em);
W == 3em;
So, each duo of 'a', 'm' and 'x' should fill one and only 1
line box. There are 15 'a' duos and 15 'm' duos; therefore,
the 3 inner column boxes of each first 2 inner
multi-column elements should use 5 line boxes.
The 1st column box of last inner multi-column
(the blue one with 'x' duos) should have 'x1',
'x2' and 'x3' duos filling 3 line boxes.
The 2nd column box of last inner multi-column should
have 'x4', 'x5' and 'x6' duos filling 3 line boxes.
The 3rd column box of the last inner multi-column should
have 'x7' and 'x8' duos filling 2 line boxes.
*/
]]></style>
</head>
<body>
<div>
<div> a1 a2 a3 a4 a5 a6 a7 a8 a9 a0 a1 a2 a3 a4 a5 </div>
<div> m1 m2 m3 m4 m5 m6 m7 m8 m9 m0 m1 m2 m3 m4 m5 </div>
<div> x1 x2 x3 x4 x5 x6 x7 x8 </div>
</div>
</body>
</html>
Codebase Browser
chromium