<link href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<div class="col-sm-12 view">
<div class="main">
<div class="col-sm-5 top-wel">Test Your Responsive Website !!</div>
<div class="col-sm-2 box">
<div class="col-sm-2 device" onclick="a()"><i class="fa fa-desktop" style="font-size:20px;"></i></div>
<div class="col-sm-2 device" onclick="b()"><i class="fa fa-tablet" style="font-size:20px; -webkit-transform:rotate(90deg);"></i></div>
<div class="col-sm-2 device" onclick="c()"><i class="fa fa-tablet" style="font-size:20px;"></i></div>
<div class="col-sm-2 device" onclick="d()"><i class="fa fa-mobile" style="font-size:20px; -webkit-transform:rotate(90deg);"></i></div>
<div class="col-sm-2 device" onclick="e()"><i class="fa fa-mobile" style="font-size:20px;"></i></div>
</div>
<div class="col-sm-4 box">·</div>
<div class="col-sm-1 check" onclick="a()">auto ···········▼
<div class="col-sm-12 check-in" style="margin-top:20px;" onmouseover="f()">280 px</div>
<div class="col-sm-12 check-in" onmouseover="g()">320 px</div>
<div class="col-sm-12 check-in" onmouseover="e()">480 px</div>
<div class="col-sm-12 check-in" onmouseover="i()">568 px</div>
<div class="col-sm-12 check-in" onmouseover="j()">768 px</div>
<div class="col-sm-12 check-in" onmouseover="k()">1024 px</div>
<div class="col-sm-12 check-in" onmouseover="l()">1190 px</div>
<div class="col-sm-12 check-in" onmouseover="m()">1300 px</div>
</div>
</div>
</div><iframe src="YOUR OFFLINE URL HERE" height="100%" id="respons" class="site"></iframe>