//global variables

var timerID = null;
var timerOn = false;
var timecount = 500;

function setcurrent(){
var currentpage = document.getElementById("comprehensiveintro");
currentpage.style.display="block";
}


function initnav(){
setcurrent();
}

// show or hide the layers
function showLayer(layerName){
document.getElementById(layerName).style.display="block";
}

function hideLayer(layerName){
document.getElementById(layerName).style.display="none";
}

function hideAll(){
hideLayer('comprehensiveintro');
hideLayer('comprehensive1');
hideLayer('comprehensive2');
hideLayer('comprehensive3');
hideLayer('comprehensive4');
hideLayer('comprehensive5');
hideLayer('comprehensive6');
hideLayer('comprehensive7');
hideLayer('comprehensive8');
hideLayer('comprehensive9');
hideLayer('comprehensive10');
hideLayer('comprehensive11');
hideLayer('comprehensive12');
hideLayer('comprehensive13');
hideLayer('comprehensive14');
}