adjust only iframe src from youtube
<p>how can I adjust the width and height for all iframe that has only youtube link</p>

<pre><code>&lt;iframe width="420" height="315" frameborder="0" allowfullscreen="" src="http://www.youtube.com/embed/xbGv2T456dfg3"&gt;
</code></pre>

<p>because I have some the uses iframe also but I only need to adjust all iframe that has a youtube link.</p>

<p>css</p>

<pre><code>iframe {width:560px;height:316px;}
</code></pre>

<p>need help on this</p>
