.div1 {
  width: 50%;
  max-width: 900px;
}

#text,
#output {
  width: 100%;
  min-height: 200px;
  padding: 0.6rem;
}

@media (max-width: 1200px) {
  .div1 {
    width: 70%;
  }
}

@media (max-width: 768px) {
  .div1 {
    width: 90%;
  }

  .div2 {
    flex-direction: column !important;
    align-items: center !important;
    width: 100%;
  }

  #text,
  #output {
    width: 100% !important;
    font-size: 1rem;
  }

  button {
    width: 100%;
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: 1.2rem !important;
    text-align: center;
  }

  button {
    font-size: 1.1rem !important;
    padding: 0.6rem;
  }
}