Responsive iframe width and height hack using an image to maintain the aspect ratio. Thanks to http://jsfiddle.net/Masau/7WRHM/

css.scss

.map {
	position: relative;
	min-height: 200px;

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

html.html

<div class="col">
	<div class="map">
		<img class="ratio" src="inc/img/16x9.gif"/>
		<iframe frameborder="0" scrolling="no" marginheight="0" marginwidth="0"></iframe>
	</div>
</div>