.modal {
    position: fixed;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: none;
    z-index: 1000;
    overflow: auto;
    -webkit-box-align: center;
    -webkit-box-pack: center;
}
.pr {
    position: relative;
}

.mask {
    background: #000;
    opacity: 0.6;
    z-index: 200;
    position: fixed;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    filter: progid:DXImageTransform.Microsoft.Alpha(opacity=70);
}

.modal-box {
    position: absolute;
    top: 10px;
    left: 0;
    bottom: 0;
    right: 0;
    margin: auto;
    z-index: 1111;
    display: none;
    box-sizing: border-box;
    font-size: 16px;
    color: #313131;
    background-repeat: no-repeat;
    background-position: top center;
    background-size: 100%;
    border-radius: 30px;
}