var acc = document.getElementsByClassName("accordion");
            var i; 
            for (i = 0; i < acc.length; i++) {
              acc[i].addEventListener("click", function() {
                this.classList.toggle("active");
                var subMenu = this.nextElementSibling;
                if (subMenu.style.maxHeight) {
                    subMenu.style.maxHeight = null;
                } else {
                    subMenu.style.maxHeight = subMenu.scrollHeight + "px";
                } 
              });
            }

function nordbahnview(){
  var viewp = vcs.vcm.Framework.getInstance().viewpoints.NordBView
  vcs.vcm.Framework.getInstance().getActiveMap().gotoViewPoint(viewp);

  document.getElementById("UmfrageOne").style.display = "none";
  document.getElementById("NordbahnhofInfo").style.display = "block";
  document.getElementById("Navigation").style.display = "none";
  document.getElementById("projektOne").style.display = "none";
  document.getElementById("Energiekonzept").style.display = "none";
  document.getElementById("IntroProj").style.display = "none";
  document.getElementById("Expertenmodus").style.display = "block";
  showgraph();
  
}

var expstate = false;
function onoff(){

  if(expstate == false){
    var element = document.getElementById("menustuff");
    element.classList.remove("hidden");
    expstate = true;
  }else{
    var element = document.getElementById("menustuff");
    element.classList.add("hidden");
    expstate = false;
  }
}