.center {
    width: 100%;
    margin: 0 auto;
}


.main_yx-video{
    width: 100%;
    background: #000;
    position: relative;
}
.main_yx-video .main_yx-btn{
    width: 76px;
    height: 76px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-50%);
    cursor: pointer;
    z-index: 2;
}
.main_yx-video video{
    display: block;
    width: 100%;
    height: auto;
}