body {

  margin: 0;

  background-color: #000;

  display: flex;

  align-items: center;

  justify-content: center;

  height: 100vh;

  font-family: 'Courier New', Courier, monospace;

}



#clock {

  display: flex;

  font-size: 15vw;

  color: #0f0;

  text-shadow: 0 0 10px #0f0, 0 0 20px #0f0, 0 0 30px #0f0;

}



#clock span {

  transition: all 0.2s ease-in-out;

}



@media (max-width: 768px) {

  #clock {

    font-size: 20vw;

  }

}



@media (max-width: 480px) {

  #clock {

    font-size: 25vw;

  }

}