.vidbacking-active-body-back{
    position: fixed;
    z-index: -100;
    min-width: 100%;
    min-height: 100%;
    top: 50%;
    left: 50%;
    background-size: cover;
    overflow: hidden;
    opacity: 1;
    transition: 2s opacity;
    transform: translateX(-50%) translateY(-50%);
}

.vidbacking-active-block-back{
    position: absolute;
    min-width: 100%;
    min-height: 100%;
    height: auto;
    width: auto;
    z-index: -100;
    top: 50%;
    left: 50%;
    transform: translateX(-50%) translateY(-50%);
}

.vidbacking{
    display: none;
}
.vidmask-body-back{
    background: url(../images/videooverlay.png) repeat;
    opacity: 0.4;
    min-height: 100%;
    min-width: 100%;
    position: fixed;
    top: 0;
    left: 0;
    z-index: -50;
    display: block;
}
.vidmask-block-back{
    background: url(../images/videooverlay.png) repeat;
    opacity: 1;
    min-height: 100%;
    min-width: 100%;
    position: absolute;
    top: 0;
    left: 0;
    height: auto;
    width: auto;
    z-index: -50;
    display: block;
}
.clearfix{display:block;clear:both;float:none;}
.index_video{ height: 800px; display: flex; overflow: hidden;}

.video-back{ width:100%;align-self: center;text-align:center; }


.video-back h2{display:block;text-align:center;color:#fff;font-size:50px;}
.video-back p{display:block;color:#fff;margin:0px;padding:0px;margin-bottom:20px;}
.video-back img{width:150px;}
.jq22-demo a{ color: aliceblue; font-family: "微软雅黑"; font-size: 20px; text-decoration: none; padding-left: 10px; padding-right: 10px; font-weight: bold;text-shadow:2px 2px 4px #000; }

@media screen and (max-width:1200px){
    .index_video{ height: 600px; display: flex;}
    .video-back h2{ font-size: 40px ;color:#fff;}
}
@media screen and (max-width:992px){
    .index_video{ height: 500px; display: flex;}
    .video-back h2{ font-size: 30px;color:#fff; }
}
@media screen and (max-width:768px){
    .index_video{ height: 300px; display: none;}
    .video-back h2{ font-size: 20px ;color:#fff;}
}