<body>
  <header>
    ヘッダ
  </header>
  <main>
    コンテンツ
  </main>
  <footer>
    フッタ
  </footer>
</body>
html{
  min-height: 100%;
  position: relative;
}
body {
  margin: 0;
  padding: 0;
  margin-bottom: 100px;
}
header {
  width: 100%;
  background: #ccdd33;
}
main {
}
footer {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100px;
  background: #44aa33;
}

External CSS

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External JavaScript

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