.ymodal {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 999;
    display: none;
}

.ymodal-dialog {
    position: relative;
}

.ymodal-backdrop {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 998;
    background-color: #000;
    opacity: 0.8;
}