.modal {
    display: none;
}

.modal.is-active {
    display: block;
}

.modal__overlay {
    width: 100%;
    height: 100%;
    position: fixed;
    top: 0;
    left: 0;
    background: rgba(0, 0, 0, 0.7);
    z-index: 11;
}

.modal__content {
    z-index: 2;
    display: block;
    width: 550px;
    height: 345px;
    background-color: transparent;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-image: url("banner_pc.jpg");
    background-position: center center;
    background-repeat: no-repeat;
    z-index: 11;
}

.modal__close {
    position: absolute;
    right: -30px;
    top: -30px;
}