body {
      font-family: Arial, sans-serif;
      text-align: center;
      margin-top: 50px;
      background: #A4D0EC;
      color: white;
  }

  h1 {
      font-size: 1.5rem;
  }

  #number {
      font-size: 4rem;
      margin: 20px;
      color: #333;
  }

  button {
      padding: 15px 25px;
      font-size: 1.2rem;
      margin: 10px;
      border: none;
      border-radius: 8px;
      cursor: pointer;
  }

  #callBtn {
      background-color: #28a745;
      color: white;
  }

  #resetBtn {
      background-color: #dc3545;
      color: white;
  }

  #history {
      margin-top: 20px;
      font-size: 1rem;
      max-width: 400px;
      margin-left: auto;
      margin-right: auto;
  }

  #voiceSelect {
      font-size: 0.6rem;
      padding: 5px;
      margin-top: 10px;
  }