.blocVideo {
    position: relative;
    display: flex;
}

.blocVideo:before {
    content: '';
    position:absolute;
    right: 0;
    top: 0;
    bottom:  0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);    
}
.play {
    position: absolute;
    top: 0;
    height: 100%;
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    flex-direction:column;
}