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- This WPT test may be referenced by the following Test IDs:
- /css/CSS2/visuren/fixed-pos-stacking-001.xht - WPT Dashboard Interop Dashboard
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
<head>
<title>CSS test: fixed positioning makes a stacking context</title>
<link rel="help" href="http://www.w3.org/TR/CSS22/visuren.html#z-index" title="9.9.1 Specifying the stack level: the 'z-index' property" />
<link rel="help" href="http://www.w3.org/TR/CSS22/changes.html#s.9.9.1" title="C.1 Changes since the Recommendation of 7 June 2011" />
<meta name="assert" content="auto The stack level of the generated box in the current stacking context is 0. If the box has 'position: fixed' or if it is the root, it also establishes a new stacking context." />
<link rel="match" href="fixed-pos-stacking-001-ref.xht" />
<link rel="author" title="Bert Bos" href="mailto:bert@w3.org" />
<style type="text/css">
div {width: 5em; height: 2em}
/* absolute with 'z-index: auto' does not create a stacking context */
#absolute {position: absolute; left: 1em; top: 3em; background: green}
#absolute div {position: absolute}
#absolute div div {position: absolute; z-index: -1; background: red}
/* fixed with 'z-index: auto' *does* create a stacking context */
#fixed {position: fixed; left: 10em; top: 3em; background: red}
#fixed div {position: absolute}
#fixed div div {position: absolute; z-index: -1; background: green}
</style>
</head>
<body>
<p>There should be no red.</p>
<div id="absolute">
<div>
<div></div>
</div>
</div>
<div id="fixed">
<div>
<div></div>
</div>
</div>
</body>
</html>