<header>
  <h2>Header</h2>
</header>

<main>
  <h2>Main Content</h2>
</main>

<footer>
  <h2>Footer</h2>
</footer>

@import url("https://fonts.googleapis.com/css?family=Gochi+Hand");

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  width: 100vw;
  min-height: 100vh;
  margin: 0;
  background-color: #291642;
  font-family: "Gochi Hand", sans-serif;
  font-size: 100%;
  letter-spacing: 0.1rem;
  color: #fff;

  display: flex;
  flex-direction: column;
}

header,
main,
footer {
  display: flex;
  justify-content: center;
  align-items: center;
}

header {
  background-color: #2196f3;
  min-height: 15vh;
}
main {
  background-color: #f4f4f4;
  color: #444;
  overflow: hidden;
  resize: vertical;
}

footer {
  min-height: 24vh;
  background-color: #222;
}

main {
  flex: 1 0 auto;
  min-height: 0;
}