#payBtn {
      background: #00ff66;
      color: black;
      font-weight: bold;
      padding: 5px 25px;
      border: none;
      border-radius: 8px;
      font-size: 16px;
      cursor: pointer;
    }

    #payBtn:hover {
      background: #00ff11;
    }
    /* Popup background */
    .popup {
      display: none; 
      position: fixed;
      z-index: 1000;
      left: 0;
      top: 0;
      width: 100%;
      height: 100%;
      background: rgba(0,0,0,0.6);
      justify-content: center;
      align-items: center;
    }

    /* Popup content */
    .popup-content {
      background: white;
      padding: 20px;
      border-radius: 12px;
      text-align: center;
      max-width: 400px;
      box-shadow: 0px 4px 20px rgba(0,0,0,0.3);
      position: relative;
      animation: fadeIn 0.3s ease-in-out;
    }

    /* QR Code */
    .popup-content img {
      width: 350px;
      margin-top: 10px;
    }
    .popup-content h3{
      color: black;
    }

    /* Close button */
    .close {
      position: absolute;
      top: 10px;
      right: 15px;
      font-size: 20px;
      font-weight: bold;
      color: #333;
      cursor: pointer;
    }

    .close:hover {
      color: red;
    }

    @keyframes fadeIn {
      from {opacity: 0; transform: scale(0.9);}
      to {opacity: 1; transform: scale(1);}
    }

    /* Popup background */
    .popup-overlay {
      position: fixed;
      top: 0; left: 0;
      width: 100%; height: 100%;
      background: rgba(0,0,0,0.5);
      display: none;
      justify-content: center;
      align-items: center;
      z-index: 1000;
    }
    /* form submitted */
    .popup-box {
      background: #fff;
      color: black;
      padding: 20px;
      border-radius: 15px;
      text-align: center;
      width: 350px;
      animation: fadeIn 0.5s ease-in-out;
      box-shadow: 0px 8px 25px rgba(0,0,0,0.3);
    }

    .popup-box h3 {
      color: #28a745;
      margin-bottom: 10px;
    }

    .popup-box p {
      font-size: 16px;
      margin-bottom: 20px;
    }

    .popup-box button {
      background: #28a745;
      color: white;
      border: none;
      padding: 5px 20px;
      border-radius: 8px;
      cursor: pointer;
      font-size: 16px;
      transition: 0.3s;
    }

    .popup-box button:hover {
      background: #218838;
    }

    /* Fade in animation */
    @keyframes fadeIn {
      from {opacity: 0; transform: scale(0.9);}
      to {opacity: 1; transform: scale(1);}
    }