Jsカウントダウン

      var timer = setInterval(function(){
            if ( time > 1) {
                time -= 1;
                var minute = parseInt( time / 60 );
                var second = parseInt( time % 60 );
                $('.timer').html( minute+':'+second );
            } else { 
                clearInterval( timer );//     
            }
      }, 1000);