After selecting Donate button pop up window appears dimmed out

Hi
Thank you for feedback us
I check and see have a few conflict style CSS and I have fix it for you
in file: ..../components/com_jux_charity_hub/assets/css/cause_detail.css and add code CSS in end file

.tm-page-container,
.tm-page {
z-index: inherit!important;
}
div.modal {
z-index: 9999!important;
}
.modal-backdrop {
background-color: #000!important;
}

Hope it will help you
Thanks