var n;
$(function() {	
	n = parseInt( $("#count_down").text() );
	window.iId = window.setInterval( "count_down()", 1000 );
});

function count_down() {
	n -= 1;
	$("#count_down").text(n);
	if( n ==0 ) {
		window.clearInterval(iId);
		//window.location = "/sign-in/";
		window.location = "/";
	}
}