html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
}
#main-div {
  min-height: 100%;
  position: relative;
}
#body {
  padding: 10px;
  padding-bottom: 60px; /* Height of the footer */
}
#footer {
  position: absolute;
  bottom: 0;
  width: 100%;
  height: 60px; /* Height of the footer */
}