.slider-portlet{
    position:relative;
    overflow:hidden;
    padding:0;
    margin:0;
    width:100%;
}

.slider-under, .slider-over{
    position:absolute;
    top:0px;
    left:0px;
    width:100%;
    height:100%;
}

.slider-over{
    z-index:1;
    background-color:inherit;
}

.slider-under{

}