function changeStyleById(welches,nav) {

	               if (document.getElementById) {
                        	// alle ausblenden
                         document.getElementById("1").style.display = "none";
                         document.getElementById("2").style.display = "none";
                         document.getElementById("3").style.display = "none";
                         document.getElementById("4").style.display = "none";
                         document.getElementById("5").style.display = "none";
                         document.getElementById("6").style.display = "none";

                         // Uebergebene ID Aendern
	                  var bla = document.getElementById(welches);
                           var stil = (bla.style.display == "block") ? "none" : "block";
	                  bla.style.display = stil;
	                  }
	           }

	    function alle() {

	               if (document.getElementById) {
                        	// alle einblenden
                         document.getElementById("1").style.display = "block";
                         document.getElementById("2").style.display = "block";
                         document.getElementById("3").style.display = "block";
                         document.getElementById("4").style.display = "block";
                         document.getElementById("5").style.display = "block";
                         document.getElementById("6").style.display = "block";

	                  }
	           }