.is_not_on_nih_network .restrict_media .wp-block-video:after
,.is_not_on_nih_network .restrict_media .wp-video:after {
    position: absolute;
    opacity: 1;
    color: #fff;
    content:'You must be using the NIH VPN or local network (on site) to access to this video.';
    width:100%; 
    height:100%;
    top:0; 
    left:0;
    background:rgba(0,0,0,0.6);
    font-size: 20px;
    padding: 18px;
    z-index: 9999;
}

.is_not_on_nih_network .restrict_media .wp-block-video
,.is_not_on_nih_network .restrict_media .wp-video {
    position:relative;
    width:100%;
    vertical-align:top;
}