Responsiveness is the new trend in WordPress Theme Industry,Nobody likes to maintain a separate plugin or separate theme for presenting your site in mobile devices.
Though all most every WordPress theme now comes with a mobile responsive design but you cannot guarantee that it is also optimized for displaying iFrame embeds such as the Youtube videos.
Making Embedded Videos responsive
Paste the following code in your current themes style.css file
.video-container { position: relative; padding-bottom: 56.25%; padding-top: 30px; height: 0; overflow: hidden; } .video-container iframe, .video-container object, .video-container embed { position: absolute; top: 0; left: 0; width: 100%; height: 100%; } .entry-content img, .entry-content iframe, .entry-content object, .entry-content embed { max-width: 100%; }
Now whenever you embed a video add the div tag with class .video-container
.
<div class="video-container"> Video Embed code </div>
For example embedding a youtube video
<div class="video-container"> <iframe width="560" height="315" src="http://www.youtube.com/embed/S95J5BowMmk" frameborder="0" allowfullscreen></iframe> </div>
Here you can check the demo.
In title I just mentioned Youtube videos but actually you use it on any embeds such as Vimeo Video embeds,Slideshare etc.
If you prefer plugins rather than modifying theme then use Advanced Responsive Video Embedder or Fluid Video Embeds
via Webdesignerwall