var Ring = Container.expand(function (size) {
	var self = Container.call(this);
	self.size = size;
	var ringGraphics = self.createAsset('ring', 'Ring for the game', 0.5, 0.5);
	ringGraphics.scale.y = 1 - size * 0.15;
	ringGraphics.rotation = Math.PI / 2;
	self.type = Math.floor(Math.random() * 5);
	var colors = [0xFF9999, 0xFFFF99, 0x99FF99, 0x9999FF, 0xFF99FF];
	ringGraphics.tint = colors[self.type];
});
var Stack = Container.expand(function () {
	var self = Container.call(this);
	self.rings = [];
	self.targetY = self.y;
	self.move = function () {
		if (self.y !== self.targetY) {
			if (Math.abs(self.y - self.targetY) < 1) {
				self.y = self.targetY;
			} else {
				self.y += (self.targetY - self.y) / 10;
			}
		}
	};
	var stackBG = self.createAsset('background', 'Background for the game', 0.5, 0.5);
	self.setBGAlpha = function (alpha) {
		stackBG.alpha = alpha;
	};
	self.setBGAlpha(0);
	var rod = self.createAsset('rod', 'Rod for the game', 0.5, 0.5);
	self.addRing = function (ring) {
		if (self.rings.length < 5) {
			self.rings.push(ring);
			self.addChild(ring);
			ring.y = 358 / 2 - self.rings.length * ring.height + ring.height / 2 - 5;
		}
	};
	self.removeRing = function () {
		if (self.rings.length > 0) {
			var ring = self.rings.pop();
			return ring;
		}
	};
	self.checkRings = function () {
		if (self.rings.length === 5 && self.rings[0].size === 0) {
			var type = self.rings[0].type;
			for (var i = 1; i < 5; i++) {
				if (self.rings[i].type !== type || self.rings[i].size !== i) {
					return false;
				}
			}
			return true;
		}
		return false;
	};
	self.on('down', function () {
		if (Game.selectedStack) {
			if (self.rings.length < 5) {
				var ring = Game.selectedStack.removeRing();
				if (ring) {
					self.addRing(ring);
				}
			}
			Game.selectedStack.setBGAlpha(0);
			Game.selectedStack = null;
		} else {
			Game.selectedStack = self;
			self.setBGAlpha(0.5);
		}
	});
});
var Game = Container.expand(function () {
	var self = Container.call(this);
	self.stacks = [[], [], [], [], []];
	self.selectedStack = null;
	self.score = 0;
	var background = self.createAsset('game_background', 'Background for the game', 0.5, 0.5);
	background.zIndex = -1;
	background.x = 2048 / 2;
	background.y = 2732 / 2;
	background.alpha = .3;
	var stackContainer = self.addChild(new Container());
	stackContainer.x = 368 / 2 + 79;
	stackContainer.y = 368 / 2 + 500;
	var scoreTxt = new Text2('0', {
		size: 150,
		fill: '#ffffff',
		font: 'Impact',
		dropShadow: true,
		dropShadowColor: '#000000'
	});
	scoreTxt.setText(self.score);
	scoreTxt.anchor.set(.5, 0);
	LK.gui.topCenter.addChild(scoreTxt);
	for (var row = 0; row < 5; row++) {
		for (var col = 0; col < 5; col++) {
			var stack = stackContainer.addChild(new Stack());
			stack.x = col * (stack.width + 10);
			stack.y = row * (stack.height + 10);
			stack.targetY = stack.y;
			if (!(row === 2 && col === 2)) {
				for (var i = 0; i < 5; i++) {
					var ring = new Ring(i);
					stack.addRing(ring);
				}
			}
			self.stacks[row][col] = stack;
		}
	}
	LK.on('tick', function () {
		for (var row = 0; row < self.stacks.length; row++) {
			for (var col = 0; col < self.stacks[row].length; col++) {
				if (self.stacks[row][col] && self.stacks[row][col].checkRings()) {
					self.stacks[row][col].destroy();
					self.stacks[row][col] = null;
					self.score += 1;
					scoreTxt.setText(self.score);
				}
			}
		}
		for (var row = self.stacks.length - 1; row >= 0; row--) {
			for (var col = 0; col < self.stacks[row].length; col++) {
				if (self.stacks[row][col] === null && row > 0 && self.stacks[row - 1][col] !== null) {
					self.stacks[row][col] = self.stacks[row - 1][col];
					self.stacks[row - 1][col] = null;
					self.stacks[row][col].targetY += self.stacks[row][col].height + 10;
				}
				if (self.stacks[0][col] === null) {
					var newStack = new Stack();
					for (var i = 0; i < 5; i++) {
						var ring = new Ring(i);
						newStack.addRing(ring);
					}
					self.stacks[0][col] = newStack;
					stackContainer.addChild(newStack);
					newStack.x = col * (newStack.width + 10);
					newStack.y = -newStack.height;
					newStack.targetY = 0;
				}
				if (self.stacks[row][col]) {
					self.stacks[row][col].move();
				}
			}
		}
	});
});

===================================================================
--- original.js
+++ change.js
@@ -59,11 +59,13 @@
 				if (ring) {
 					self.addRing(ring);
 				}
 			}
+			Game.selectedStack.setBGAlpha(0);
 			Game.selectedStack = null;
 		} else {
 			Game.selectedStack = self;
+			self.setBGAlpha(0.5);
 		}
 	});
 });
 var Game = Container.expand(function () {