body {
  display:flex;
  flex-direction:column;
  align-items: center;
  justify-content: center; 
  height: 100vh;
  margin: 0;
  padding: 0;
  background-color: #003300;
  font-family: Arial, sans-serif;
  color: #fff;

  @supports (height: 100dvh) {
    height: 100dvh;
  }
}

area:hover {
  border: 1px solid yellow;
}