function toggle_visibility(id) {
	var e = document.getElementById(id);
	
	if(e.style.display == '')
	e.style.display = 'block';
	else
	if(e.style.display == 'none')
	e.style.display = 'block';
	else
	e.style.display = 'none';
}

function visibility_all(num){

   
    for(id=1;id<num;id++)
    {
        var e = document.getElementById(id);
	    if(e.style.display == 'none')
	    e.style.display = 'block';
	    else
	    e.style.display = 'none';
	   
	}
}

 function showLayer(num)
{

    for(id=1;id<num;id++)
    {
        var targetElement = document.getElementById(id);
        targetElement.style.display = 'block';
        document.getElementById('a'+id).className = 'less';
    }
}
function hideLayer(num)
{
    for(id=1;id<num;id++)
    {
        var targetElement = document.getElementById(id);
        targetElement.style.display = 'none';
        document.getElementById('a'+id).className = 'more';

    }
}
function getRef(obj){
        return (typeof obj == "string") ?
        document.getElementById(obj) : obj;
}

function toggleClassName(obj, class1, class2){
        obj= getRef(obj);
        if(!obj.isClass1){
                obj.className= class1;
                obj.isClass1= true;
        }
        else{
                obj.className= class2;
                obj.isClass1= false;
        }
}