#calculator {
      margin: 0 auto;
      max-width: 500px;
      background-color: #fff;
      padding: 20px;
      border-radius: 5px;
      box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    }

    label {
      display: block;
      font-weight: bold;
      margin-bottom: 10px;
    }

    input[type="number"],
    select {
      padding: 5px;
      font-size: 16px;
      border-radius: 5px;
      border: none;
      box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
      width: 100%;
      margin-bottom: 20px;
    }

button[type="button"] {
    background-color: #4CAF50;
    border: none;
    color: white;
    padding: 10px 20px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
    border-radius: 5px;
}

button[type="reset"] {
    background-color: #f44336;
    color: white;
    border: none;
    padding: 10px 20px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
    border-radius: 4px;
}

button:hover {
    opacity: 0.8;
}

    .result {
      font-size: 20px;
      font-weight: bold;
      margin-top: 20px;
    }

    @media only screen and (max-width: 600px) {
      #calculator {
        max-width: 90%;
      }
    }