<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title> CSS Values and Units Test: Range clamping into calc() expressions </title> <meta name="assert" content=" A calc expression can evaluate to a value which is outside the validity range. If it does, this value must be clamped into the range. The declaration must not be ignored. " /> <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/200-200-green.html" /> <style type="text/css"> html, body { margin: 0px; padding: 0px; } html { background: white; overflow: hidden; } #outer { background: green; width: 200px; height: 200px; } #outer { border-radius: 10px; border-radius: calc(-10px); } </style> </head> <body> <div id="outer"></div> </body> </html>