function linkToYoutube(link, ops) {

​

  var o = $.extend({

    width: 480,

    height: 320,

    params: ''

  }, ops);

  var id = /\?v\=(\w+)/.exec(link)[1];

​

  return '<iframe style="display: block;"'+

    ' class="youtube-video" type="text/html"'+

    ' width="' + o.width + '" height="' + o.height +

    ' "src="http://www.youtube.com/embed/' + id + '?' + o.params +

    '&wmode=transparent" frameborder="0" />';

}

​

$('a').each(function(){

  var link = $(this).attr('href');

  $(this).html( linkToYoutube(link, { params: 'theme=light' }) );

});