#myModal .modal-dialog {
    width: 45% !important;
    max-width: 45%;
    height: 100vh;
    margin: 0 auto;
}

#myModal .modal-content {
    height: 100vh;
    display: flex;
    flex-direction: column;
}

#myModal .modal-body {
    overflow-y: auto;
    flex: 1 1 auto;
}

@media screen and (max-width: 768px) {
    #myModal .modal-dialog {
        width: 100% !important;
        max-width: 100%;
        margin: 0;
    }
}