#popup_this {
    top: 50%;
    left: 50%;
    text-align:center;
    margin-top: 20px;
    margin-left: 20px;
    position: fixed;
    background: #f4f4f4;
    padding: 30px;
}
.b-close {
    position: absolute;
    right: 0;
    top: 0;
    cursor: pointer;
    color: #fff;
    background: #ff0000;
    padding: 5px 10px;
}