<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title> CSS Values and Units Test: Calc() inside calc() </title> <meta name="assert" content=" The calc() function notation is allowed inside a calc() notation. " /> <link rel="author" title="François REMY" href="mailto:fremycompany.developer@yahoo.fr" / > <link rel="help" href="http://www.w3.org/TR/css3-values/#calc-notation"/> <link rel="match" href="reference/all-green.html" /> <style type="text/css"> html, body { margin: 0px; padding: 0px; } html { background: red; overflow: hidden; } #outer { position: absolute; top: 0px; left: 0px; background: green; width: 100%; } #outer { height: calc(calc(100%)); </style> </head> <body> <div id="outer"></div> </body> </html>