wrapper for responsive iframe

<style type="text/css">
.videoWrapper {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 */
    padding-top: 25px;
    height: 0;
}
.videoWrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}
</style>
<p> <div class="videoWrapper"><iframe src="http://fast.wistia.net/embed/iframe/vx69rggb0a?autoPlay=true&amp;controlsVisibleOnLoad=true&amp;endVideoBehavior=reset&amp;version=v1&amp;videoHeight=422&amp;videoWidth=750&amp;volumeControl=true" width="750" height="422" frameborder="0" scrolling="no"></iframe></div></p>