body {
      font-family: 'Poppins', sans-serif;
      color: white;
      display: flex;
      justify-content: center;
      align-items: center;
      height: 100vh;
      margin: 0;
    }

    .atm {
      background: black;
      padding: 30px 40px;
      width: 350px;
      text-align: center;
      border: 2px solid #00ffc6;
    }

    h1 {
      margin-bottom: 20px;
    }

    input {
      width: 80%;
      padding: 10px;
      border: none;
      text-align: center;
      font-size: 18px;
      outline: none;
    }

    button {
      margin-top: 20px;
      padding: 10px 20px;
      background: #00ffc6;
      color: #000;
      border: none;
      cursor: pointer;
      font-size: 16px;
      font-weight: bold;
      transition: 0.3s;
    }

    button:hover {
      background: #00cfa2;
    }

    .output {
      color: #000;
      margin-top: 25px;
      background: white;
      padding: 15px;
      font-size: 16px;
    }

    .note {
      margin: 5px 0;
    }