//---------------------NAV PANEL-------------------
function nav_bar(i){

	if(offset == 0)
	{
		document.getElementById("btn_pre").style.visibility = "hidden";
		document.getElementById("btn_next").style.visibility = "visible";
	}else
	{
		document.getElementById("btn_pre").style.visibility = "visible";
		document.getElementById("btn_next").style.visibility = "visible";
	}
	if(offset+20 > i)
	{
		document.getElementById("btn_next").style.visibility = "hidden";
    }
	if (i == 0)
	{
		document.getElementById("nav_panel_page").style.visibility = "hidden";
		document.getElementById('nav_panel').innerHTML = result_zero_en();
		
	}
}
    
function nav_pre(){
    offset -= 20;
	loadXMLDoc();
}
    
function nav_next(){
	offset += 20;
	loadXMLDoc();
}
function nav_exp_all(){
	for(i=0;i<21;i++)
	{
		$('#content'+i).slideDown('slow');
	}
}
function nav_hide_all(){
	for(i=0;i<21;i++)
	{
		$('#content'+i).slideUp('slow');
	}
}
//---------END------NAV PANEL-----------------------------