Fullscreen
HTML
<div class="portblock">CLICK</div>
<div class="map"><div class="portblock">CLICK</div></div>
<div class="map"><div class="portblock">CLICK</div></div>
CSS
.map {
width: 400px;
height: 200px;
background:#ccc;
}
.map.fullscreen {
width:100%;
height: 100%;
}
JavaScript
$(".portblock").click(function() {
$(".map").toggleClass("fullscreen")
});