function swap_image(i, str) {
	 newImage = "url(img/mission_bg"+i+".jpg)";
     document.getElementById('pic_container').style.backgroundImage = newImage;
	 document.getElementById('mission_desc').innerHTML = str;
	 for (j=1;j<=4;j++) {
	  if (j==i)document.getElementById('pg'+j).className = 'pag_sel';
	  else document.getElementById('pg'+j).className = 'pag';
	}
}

var timeout	= 500;
var closetimer	= 0;
var ddmenuitem	= 0;


function show_submenu(id) {
	mcancelclosetime();
	if(ddmenuitem) ddmenuitem.style.display = 'none';
	ddmenuitem = document.getElementById('sub'+id);
	ddmenuitem.style.display = 'block';

}

function hide_submenu() {
	if(ddmenuitem) ddmenuitem.style.display = 'none';
}

function mclosetime()
{
	closetimer = window.setTimeout(hide_submenu, timeout);
}


function mcancelclosetime()
{
	if(closetimer)
	{
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}

document.onclick = hide_submenu;