Untitled

<!DOCTYPE html>
<html>
<head>
<style type="text/css">
.dashboard {
   position: relative;
   padding-bottom: 75%;  //75% is the result of height=600/width=800 ratio
   overflow: hidden;
}

.dashboard iframe {
    position: absolute;
    display: block;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

</style>
</head>
<body>
<div class="dashboard">
<iframe src="enter_your_dashboard_iframe_link_here" width="800" height="600" frameborder="0" allowfullscreen></iframe>
</div>
</body>
</html>