function login_popup()
{
    sizeX = 500;
    sizeY = 100;
    posX = (screen.width/2)-(sizeX/2);
    posY = (screen.height/2)-(sizeY/2);

  	win=window.open("inc/login_popup.php", "login_popup", "width=" + sizeX + ", height=" + sizeY + ", left=" + posX + ", top= " + posY + ", resizable=no, scrollbars=no, dependent=yes");
  	win.focus();
}

function show_hide(id_div)
{
    var div = document.getElementById(id_div);

	if(div.style.display == 'none')
		div.style.display = 'block';
	else
		div.style.display = 'none';
}