var user_agent=!(/MSIE (5\.5|6).+Win/.test(navigator.userAgent));
function min_width()
{    
    if (user_agent)
		return;
   

    
    if($(window).width()>1000)
    {
        $(".header_bg").css("width", $(window).width())
    }
    else
    {
       $(".header_bg").css("width", 1000);
    }
}