"Always bottom"-Footer

html {
  height: 100%;
  box-sizing: border-box;
}

*,
*:before,
*:after {
  box-sizing: inherit;
}

body {
  position: relative;
  margin: 0;
  padding-bottom: 6rem;
  min-height: 100%;
}

footer {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  padding: 1rem;
  background-color: #efefef;
  text-align: center;
}
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