responsive-video.css

.video-wrapper {
    position: relative;
    padding-bottom: 74.25%; /* 4:3 ratio */
    padding-top: 30px; /* IE6 workaround*/
    height: 0;
    overflow: hidden;
}

video,.videoWrapper,.video-js {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.video-js, img.vjs-poster {
    width: 100% !important;
    height: 100% !important; //these need !important because IE wants to set height/width to 100px
    max-width: 100%;
}