* {
   margin: 0;
   }
   
html, body {
   height: 100%;
   }
   
.wrapper {
   min-height: 100%;
   height: auto !important;
   height: 100%;
   margin: 0 auto -3em;
   }
   
.footer, .push {
   clear:both;
   height: 3em;
   }