.modal {
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    display: flex;
    transition: opacity 0.3s ease, visibility 0.3s ease, background-color 0.3s ease, color 0.3s ease;
    background-color: rgb(0,0,0);
    background-color: rgba(0,0,0,0.4);
    visibility: hidden;
    opacity: 0;
}

.modal.show {
    visibility: visible;
    opacity: 1;
}