Para usarlo, debemos tener la librería de jQuery agregada antes de </head>:
<script src='http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.js' type='text/javascript'/>
Y debajo, agregamos el script jquery.fitvids.js que podemos descargar desde github.
<script type='text/javascript'>
//<![CDATA[
(function( $ ){
$.fn.fitVids = function() {
var div = document.createElement("div"), ref = document.getElementsByTagName("base")[0] || document.getElementsByTagName("script")[0];
div.className = "fit-vids-style";
div.innerHTML = "<style>.fluid-width-video-wrapper {width:100%;position:relative;padding:0;} .fluid-width-video-wrapper iframe,.fluid-width-video-wrapper object,.fluid-width-video-wrapper embed {position:absolute;top:0;left:0;width:100%;height:100%;}</style>";
ref.parentNode.insertBefore(div,ref);
return this.each(function(){
var selectors = ["iframe[src^='http://player.vimeo.com']", "iframe[src^='http://www.youtube.com']", "iframe[src^='http://www.kickstarter.com']", "object", "embed"];
var $allVideos = $(this).find(selectors.join(","));
$allVideos.each(function(){
var $this = $(this), height = this.tagName == "OBJECT" ? $this.attr('height') : $this.height(), aspectRatio = height / $this.width();
$this.wrap("<div class='fluid-width-video-wrapper' />").parent(".fluid-width-video-wrapper").css("padding-top", (aspectRatio * 100)+"%");
$this.removeAttr("height").removeAttr("width");
});
});
}
})( jQuery );
//]]>
</script><script>
$(document).ready(function(){ $(".elvideo").fitVids(); });
</script><div class="elvideo">
<iframe width="425" height="349" src="http://www.youtube.com/embed/lzN5fbFlFJs" frameborder="0" allowfullscreen></iframe>
</div>var selectors = ["iframe[src^='http://player.vimeo.com']", "iframe[src^='http://www.youtube.com']", "iframe[src^='http://www.kickstarter.com']", "object", "embed"];
var selectors = ["iframe[src^='http://player.vimeo.com']", "iframe[src^='http://www.youtube.com']", "iframe[src^='http://blip.tv']", "object", "embed"];



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