convio.html

<script>
    jQuery(document).ready(function($) {
        $('iframe[src*="youtube.com"]').wrapAll('<div class="youtube-wrapper">');
        $('.youtube-wrapper').wrapAll('<div class="video-player">');
    });
</script>

<style>
    .video-player {
        clear: both;
        width: 100%;
        margin: 0 0 1em;
        overflow: hidden;
    }

    .video-player .youtube-wrapper {
        position: relative;
        width: 100%;
        height: 0;
        margin: 0 auto 1em;
        padding-bottom: 56.27%;
    }
    .video-player iframe{
        position: absolute;
        width: 100%;
        height: 100%;
    }
</style>