/**
 * Load a YouTube video after clicking a thumbnail. Use like so:
 * <img id="youtubeid" onclick="playYouTubeVideo(this)" src="thumbnail.jpg">
 */
function playYouTubeVideo(element) {
	// Create an iFrame with autoplay set to true so it starts as soon as we insert it.
	var iframe = document.createElement('iframe');
	iframe.setAttribute('src', 'https://www.youtube.com/embed/' + element.id + '?autoplay=1&autohide=1&showinfo=0&modestbranding=1');

	// Replace the thumbnail with YouTube player.
	var parent = element.parentNode;
	parent.replaceChild(iframe, element);

	// I recommended using FitVids after inserting the iFrame if responsive video is needed.
	jQuery(parent).fitVids();
}