.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
}

    .modal.active {
        display: flex;
        align-items: center;
        justify-content: center;
    }