<!DOCTYPE html> <html><head> <meta charset="utf-8"> <title> CSS Values and Units Test: Attribute references (length) </title> <meta content=" The value of referenced attribute is used correctly as a length. " name="assert"> <link href="mailto:fremycompany.developer@yahoo.fr" rel="author" title="François REMY"> <link href="http://www.w3.org/TR/css3-values/#attr-notation" rel="help"> <link href="reference/200-200-green.htm" rel="match"> <style type="text/css"> html, body { margin: 0px; padding: 0px; } html { background: white; overflow: hidden; } #outer { position: relative; background: green; } #outer { width: attr(data-test length); height: 200px; } </style> </head> <body> <div data-test="200px" id="outer"></div> </body></html>