#mainImage{
 position:relative; 
 height:342px; 
 background-color:#969696;
 width:800px;
}

#mainImage img{
    width: 800px;
    height:342px; 
}

#mainImageLeft {
    width: 0;
    height: 0;
}

#mainImageRight{
    width: 800px;
    height: 342px;
}