html, body {
  height: 100%; }

#main-content {
  min-height: 100%;
  height: auto !important;
  /* This line and the next line are not necessary unless you need IE6 support */
  height: 100%;
  margin: 0 auto -170px;
  /* the bottom margin is the negative value of the footer's height */ }

#footer, .push {
  height: 170px;
  /* .push must be the same height as .footer */ }