html {
  font-size: 2vh;
}

@media screen and (max-height: 539px) {
  html {
    font-size: 2vh;
  }
}

@media screen and (min-height: 540px) and (max-height: 900px) {
  html {
    font-size: 1.6vh;
  }
}

@media screen and (min-height: 901px) {
  html {
    font-size: 1.3vh;
  }
}