[AS3] Package Import Not Working?

I’ve been playing with AS3 and I just can’t get my package to import into my fla. My folder structure is as follows.


|Fireworks
|--|classes
|--|--Fireworks.as
|--fireworkApp.fla
|--fireworkApp.swf

As far as I know the code below, which is inside my FLA should work.


import classes.Fireworks.*;

var userInput:UInput = new UInput();

The package is as follows:


package classes.Fireworks{
    
    import flash.event.*;
    import flash.display.Sprite;
    import flash.geom.Point;
    
    public class UInput extends Sprite{
        
        public function UInput(Void){
            trace("UI Initalized");
            addListener(MouseEvent.MOUSE_DOWN, makeFirework);
        }
        
        private function makeFirework(evt:MouseEvent):Void{
            addChild(new Firework(Math.random()*100));
        }
    }
    
    class Firework extends Sprite{
        
        private var pNum:Number;
        
        public function Firework($numParticles:uint){
            
            pNum = $numParticles;
            init();
        }
        
        private function init(Void):Void{
            
            for(var i:Number = 0; i < pNum; i++){
                
                var vector:Point = new Point(Math.random()*3, Math.random()*3);
                addChild(new Particle(Math.random()*3, vector));
            }
        }
        
    }
    
    class Particle extends Sprite{
        
        public function Particle($radius:uint){
            
            var circle:Shape = new Shape();
            circle.graphics.lineStyle( 2, 0xFF0000);
            circle.graphics.beginFill( 0x0000FF, 100);
            
            circle.graphics.drawCircle($radius);
            
            addChild(circle);
        }
    }
}

Any help would be greatly appreciated :).