.modal-dialog {
    margin-top: 20vh !important;   /* adjust: 5–20vh */
}

.modal-content {
    border-color: #111 !important;
}

.modal-header {
    background-color: #333;
    border-bottom: none !important
}

.modal-footer {
    background-color: rgba(51, 51, 51, 0.4);
    border-top: none !important
}

.modal-body {
    background-color: #222;
}

.modal-backdrop.in {
    opacity: .8 !important;
}