function auf(x) {
		if(document.getElementById(x).style.display == "block") {
			document.getElementById(x).style.display = "none";
			var e = document.getElementById("hideandshow");
			e.firstChild.nodeValue = "Video ansehen";
		} 
		else{
			document.getElementById(x).style.display = "block";
			var e = document.getElementById("hideandshow");
			e.firstChild.nodeValue = "Video ausblenden";
		}
}