#countdown {
  font-size: 16px;
}

@media (min-width: 440px) and (max-width: 900.99px) {
  #countdown {
    font-size: 26px;
  }
}

@media (min-width: 901px) and (max-width: 1200.99px) {
  #countdown {
    font-size: 40px;
  }
}

@media (min-width: 1201px) {
  #countdown {
    font-size: 60px;
  }
}