.conteneur-tv { position: relative; overflow: hidden; }

.tv1 {
    background: transparent url(//i.ytimg.com/vi/Yy0K3O1BYkE/maxresdefault.jpg) no-repeat 50% 50%;
}
.tv2 {
    background: transparent url(//i.ytimg.com/vi/thYV4joIhgM/maxresdefault.jpg) no-repeat 50% 50%;
}
.tv3 {
    background: transparent url(//i.ytimg.com/vi/TjfFkZ2nCJM/maxresdefault.jpg) no-repeat 50% 50%;
}
.tv4 {
    background: transparent url(//i.ytimg.com/vi/D5iBsV8-y-I/maxresdefault.jpg) no-repeat 50% 50%;
}
.tv5 {
    background: transparent url(//i.ytimg.com/vi/xdmSPNMYBbI/maxresdefault.jpg) no-repeat 50% 50%;
}
.tv6 {
    background: transparent url(//i.ytimg.com/vi/zTCr0qeEyo0/maxresdefault.jpg) no-repeat 50% 50%;
}

.conteneur-tv>div {
	position: relative;
	background-size: 103%;
}

	.conteneur-tv>div>iframe {
	 width: 100%;
	 z-index: 1;
	 margin-top: -5px;
	 opacity: 0;
	 transition: opacity .5s;
	}
	
	.conteneur-tv>div>iframe.active {
	 opacity: 1;
	}