<html> <head> <style> div { display: -moz-box; display: -khtml-box; display: box; } .first { -moz-box-flex-group: 1; -khtml-box-flex-group: 1; box-flex-group: 1; background-color: green; -moz-box-flex: 1; -khtml-box-flex: 1; box-flex: 1; } .second { -moz-box-flex-group: 2; -khtml-box-flex-group: 2; box-flex-group: 2; background-color: red; -moz-box-flex: 1; -khtml-box-flex: 1; box-flex: 1; } </style> </head> <body> <p>You should see a 100x100 green square below. If you see any red, the test has failed. This test is checking for box-flex-group support.</p> <div style="width:100px;height:100px;background-color:red"> <div class="first"></div> <div class="second"></div> </div> </body> </html>