iframe{
            width: 100%;
			margin:0 auto;
            height: 700px;
			
        }
        .viewer{
            margin:0;
			clear:both;
        }

@media only screen and (max-width:1100px){
        iframe{
            height: 550px;
			
        }
}

@media only screen and (max-width:900px){
        iframe{
            height: 490px;
			
        }
}

@media only screen and (max-width:600px){
        iframe{
            height: 390px;
			
        }
}