#cnblogs_post_body .video1{
    height: 0;
    padding-bottom: 28.12%;/*56.25%;   16:9 */
    position: relative;
    width: 100%;
}

#cnblogs_post_body .video1 iframe{
position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
}