Access new movieclip using class

Hi! I’m new to Flash AS3, but can’t find the solution to the problem that i’ve encountered.

I took a template to create a flash game using AS3 and it uses a class that first runs a movieclip where the game is played. So when the game runs, I set a countdown timer to count down from 60 to 0. When it hits 0, I want to go to another movieclip.

Unfortunately, I have no idea how to access the other movieclip.

My code are as follows



package {
	import flash.display.Sprite;
	import flash.events.MouseEvent;
	import flash.events.TimerEvent;
	import flash.utils.Timer;
	
	public class color_match extends Sprite {
		private var ending_sc:endScene = new endScene();
		private var first_tile:colors;
		private var second_tile:colors;
		private var pause_timer:Timer;
		private var countdown_timer:Timer;
		private var score:Number=0;
		
		var colordeck:Array = new Array(1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8);
		public function color_match() {
			for (x=1; x<=4; x++) {
				for (y=1; y<=4; y++) {
					var random_card = Math.floor(Math.random()*colordeck.length);
					var tile:colors = new colors();
					tile.col = colordeck[random_card];
					colordeck.splice(random_card,1);
					tile.gotoAndStop(9);
					tile.x = (x-1)*82;
					tile.y = (y-1)*82;
					tile.addEventListener(MouseEvent.CLICK,tile_clicked);
					addChild(tile);
					score_text.visible=true;
					score_text.text="Score: "+String(score);
					timer_countdown();
					
				}
			}
		}
		public function tile_clicked(event:MouseEvent) {
			var clicked:colors = (event.currentTarget as colors);
			if (first_tile == null) {
				first_tile = clicked;
				first_tile.gotoAndStop(clicked.col);
			}
			else if (second_tile == null && first_tile != clicked) {
				second_tile = clicked;
				second_tile.gotoAndStop(clicked.col);
				if (first_tile.col == second_tile.col) {
					pause_timer = new Timer(1000,1);
					pause_timer.addEventListener(TimerEvent.TIMER_COMPLETE,remove_tiles);
					score++;
					score_text.text="Score: "+String(score);
					pause_timer.start();
				}
				else {
					pause_timer = new Timer(1000,1);
					pause_timer.addEventListener(TimerEvent.TIMER_COMPLETE,reset_tiles);
					pause_timer.start();
				}
			}
		}
		public function reset_tiles(event:TimerEvent) {
			first_tile.gotoAndStop(9);
			second_tile.gotoAndStop(9);
			first_tile = null;
			second_tile = null;
			pause_timer.removeEventListener(TimerEvent.TIMER_COMPLETE,reset_tiles);
		}
		public function remove_tiles(event:TimerEvent) {
			removeChild(first_tile);
			removeChild(second_tile);
			first_tile = null;
			second_tile = null;
			pause_timer.removeEventListener(TimerEvent.TIMER_COMPLETE,remove_tiles);
		}
		
		public function timer_countdown(){
			var count:Number = 60;

			var myTimer:Timer = new Timer(1000,count);
			
			myTimer.addEventListener(TimerEvent.TIMER, countdown);
			
			myTimer.start();

			function countdown(event:TimerEvent):void {
			time_txt.text = String((count)-myTimer.currentCount);
			if(time_txt.text == "0"){
				time_txt.text="Your score is:" +score;
				myTimer.stop();
				
				}
			}
		}

	}
}

colors and endScore are the name of the movieclips that are in my .fla file.

Please help! Sorry if this was answered before and thanks!