body {
  display: flex;
  flex-direction: column;
  margin: 0;
  min-height: 100vh;
}

footer {
  align-items: center;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 50px;
}

header {
  align-items: center;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 50px;
}

main {
  flex: 1;
}

.center-div {
  display: flex;
  justify-content: center;
}

.half-size {
  max-width: 50%;
}

.quarter-size {
  max-width: 25%;
}