body {
    font-family: monospace;
    background-color: #333;
    color: #fff;
    text-align: center;
  }
  
  #container {
    width: 75%;
    margin: 0 auto;
  }
  
  h1 {
    margin-top: 50px;
    font-size: 3em;
    text-shadow: 2px 2px 4px #000;
    text-align: center;
  }
  
  #form {
    margin-top: 50px;
  }
  
  label {
    display: block;
    margin-bottom: 15px;
    font-size: 1.5em;
  }
  
  @media only screen and (max-width: 768px) {
    input {
      width: 90%;
      height: 35px;
    }
    button {
      width: 90%;
    }
    #operation {
      width: 80%;
    }
    h1 {
      font-size: 2em;
    }
  }
  
  input {
    width: 60%;
    height: 40px;
    padding: 0 10px;
    font-size: 1.2em;
    border: none;
    border-radius: 5px;
    box-shadow: 2px 2px 4px #000;
    margin-bottom: 10px;
  }
  
  
  button {
    width: 20%;
    height: 40px;
    margin-top: 20px;
    font-size: 1.2em;
    border: none;
    border-radius: 5px;
    background-color: #fff;
    color: #333;
    box-shadow: 2px 2px 4px #000;
    cursor: pointer;
  }
  
  #result {
    margin-top: 50px;
    font-size: 1.5em;
    text-shadow: 2px 2px 4px #000;
  }
  #operation {
    width: 55%;
    height: 20px;
    padding: 0 10px;
    font-size: 1em;
    border: none;
    border-radius: 5px;
    background-color: #fff;
    color: #333;
    box-shadow: 2px 2px 4px #000;
    cursor: pointer;
    appearance: none; /* remove default styling */
    margin-bottom: 10px;
  }

  #operation:hover {
    background-color: #333;
    color: #fff;
  }
  #result {
    width: 100%;
    margin-top: 50px;
    font-size: 1.5em;
    text-shadow: 2px 2px 4px #000;
    overflow-wrap: break-word; /* wrap text at appropriate points */
  }
  #copy-button {
    background: none; /* remove default button styling */
    border: none;
    cursor: pointer;

  }

  #copy-button img {
    width: 32px; /* set the width of the image */
    height: 32px; /* set the height of the image */
  }
  #output {
    border: 1px solid #000; /* add a solid, black border */
    border-radius: 10px; /* add rounded corners to the border */
  }