body {
    margin: 0;
    height: 1000px;
}

#shadowbox {
    position: fixed;
    z-index: 998;
    height: 100%;
    width: 100%;
    background: rgba(0,0,0,0.5);
}

#banner {
    position: fixed;
    z-index: 99999;
    top: 50%; margin-top:-250px;
    left: 0px;
    min-height: 500px;
    width: 175px;
    background: #ccc;
}
#banner img {
   position:re; left:0px; top:0px;
}
#close {
    position: absolute;
    top: -20px;
    right: 0px; left:0px; text-align:center;
    font-family: Arial, Helvetica;
    font-size: 14px;
    color: #fff;
    cursor: pointer;
    font-weight: bold;
}