#demowrap {
clear: both;
margin: 30px -50px 30px 30px;
width: 780px;
height: 500px;
color: fff;
background: #fff;
}

#demowrap  iframe
{
width: 100%;
height: 100%;
border: 0;
padding: 0;
margin: 0;
display: block;
}