| <!DOCTYPE html> |
| <meta charset=UTF-8> |
| <title>CSS Filter: Establishing containing block for absolutely-positioned elements, on an inline element</title> |
| <link rel="author" title="L. David Baron" href="https://dbaron.org/"> |
| <link rel="author" title="Mozilla Corporation" href="http://mozilla.com/"> |
| <link rel="match" href="filter-cb-abspos-inline-001-ref.html"> |
| <link rel="help" href="https://drafts.fxtf.org/filter-effects-1/#FilterProperty"> |
| <link rel="help" href="https://drafts.fxtf.org/filter-effects-1/#supported-filter-functions"> |
| <meta name="flags" content=""> |
| <meta name="assert" content="A value other than none for the filter property results in the creation of a containing block for absolute and fixed positioned descendants unless the element it applies to is a document root element in the current browsing context."> |
| <meta name="assert" content="A value of 100% leaves the input unchanged."> |
| <style> |
| |
| #cb { |
| filter: brightness(100%); |
| } |
| |
| #abspos { |
| position: absolute; |
| top: 0; |
| left: 0; |
| width: 10px; |
| height: 10px; |
| background: blue; |
| } |
| |
| </style> |
| |
| <p>Filler text.</p> |
| |
| <div> |
| <span id="cb">Blue box should cover top-left corner of this sentence.<span id="abspos"></span></span> |
| </div> |
