/**** 
* Plugins
****/ 
var tween = LK.import("@upit/tween.v1");

/**** 
* Classes
****/ 
// Alien class
var Alien = Container.expand(function () {
	var self = Container.call(this);
	var alienAsset = self.attachAsset('alien', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.width = alienAsset.width;
	self.height = alienAsset.height;
	self.hp = 2; // Each alien takes 2 hits
	self.isHit = false;
	self.hitTween = null;
	// For hit flash
	self.flash = function () {
		if (self.hitTween) {
			tween.stop(alienAsset, {
				tint: true
			});
		}
		alienAsset.tint = 0xff5252;
		self.hitTween = tween(alienAsset, {
			tint: 0x8d3abf
		}, {
			duration: 200,
			easing: tween.linear,
			onFinish: function onFinish() {
				self.hitTween = null;
			}
		});
	};
	// For movement
	self.speed = 8 + Math.random() * 4; // Slightly random speed
	self.update = function () {
		// Only move downwards, do not follow rocket's x position
		self.y += self.speed;
	};
	return self;
});
// Boss Alien class (for level 7)
var BossAlien = Container.expand(function () {
	var self = Container.call(this);
	var bossAsset = self.attachAsset('alien', {
		anchorX: 0.5,
		anchorY: 0.5,
		scaleX: 1.7,
		scaleY: 1.7
	});
	self.width = bossAsset.width * 1.7;
	self.height = bossAsset.height * 1.7;
	self.hp = 6; // Boss takes 6 hits
	self.isHit = false;
	self.hitTween = null;
	self.flash = function () {
		if (self.hitTween) {
			tween.stop(bossAsset, {
				tint: true
			});
		}
		bossAsset.tint = 0xff5252;
		self.hitTween = tween(bossAsset, {
			tint: 0x8d3abf
		}, {
			duration: 200,
			easing: tween.linear,
			onFinish: function onFinish() {
				self.hitTween = null;
			}
		});
	};
	self.speed = 10; // Boss is faster
	self.update = function () {
		// Only move downwards, do not follow rocket's x position
		self.y += self.speed;
	};
	return self;
});
// Bullet class
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletAsset = self.attachAsset('bullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = -32; // Upwards
	self.power = bulletPower; // Set bullet power at creation
	self.update = function () {
		self.y += self.speed;
	};
	return self;
});
// Enemy bullet class (alien shoots at player)
var EnemyBullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletAsset = self.attachAsset('bullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	bulletAsset.tint = 0xff5252; // Red tint for enemy bullets
	self.speed = 18; // Downwards, slower than player bullet
	self.update = function () {
		self.y += self.speed;
	};
	return self;
});
// Rocket (player) class
var Rocket = Container.expand(function () {
	var self = Container.call(this);
	var rocketAsset = self.attachAsset('rocket', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.width = rocketAsset.width;
	self.height = rocketAsset.height;
	// For hit flash
	self.flashTween = null;
	// Show hit flash
	self.flash = function () {
		if (self.flashTween) {
			tween.stop(rocketAsset, {
				tint: true
			});
		}
		rocketAsset.tint = 0xff5252;
		self.flashTween = tween(rocketAsset, {
			tint: 0x4fc3f7
		}, {
			duration: 400,
			easing: tween.linear,
			onFinish: function onFinish() {
				self.flashTween = null;
			}
		});
	};
	return self;
});
// Star class for animated background stars
var Star = Container.expand(function () {
	var self = Container.call(this);
	// Use a larger ellipse for the star to make it more visible
	var size = 6 + Math.random() * 8; // Increased min and max size
	var starAsset = self.attachAsset('alien', {
		anchorX: 0.5,
		anchorY: 0.5,
		scaleX: size / 160,
		scaleY: size / 160
	});
	// Brighter color choices for more visibility
	var colorChoices = [0xffffff, 0xe3f2fd, 0xfffde7, 0xb3e5fc, 0xfff9c4];
	starAsset.tint = colorChoices[Math.floor(Math.random() * colorChoices.length)];
	self.width = size;
	self.height = size;
	self.speed = 2.5 + Math.random() * 4.5;
	// Higher minimum alpha for more visible stars
	self.alpha = 0.7 + Math.random() * 0.3;
	self.update = function () {
		self.y += self.speed;
		if (self.y > GAME_HEIGHT + 10) {
			// Respawn at top
			self.y = -10;
			self.x = 10 + Math.random() * (GAME_WIDTH - 20);
			self.speed = 2.5 + Math.random() * 4.5;
			self.alpha = 0.7 + Math.random() * 0.3;
		}
	};
	return self;
});
// Strong Alien class (tougher, faster)
var StrongAlien = Container.expand(function () {
	var self = Container.call(this);
	var alienAsset = self.attachAsset('alien', {
		anchorX: 0.5,
		anchorY: 0.5,
		scaleX: 1.2,
		scaleY: 1.2
	});
	self.width = alienAsset.width * 1.2;
	self.height = alienAsset.height * 1.2;
	self.hp = 4; // Strong alien takes 4 hits
	self.isHit = false;
	self.hitTween = null;
	self.flash = function () {
		if (self.hitTween) {
			tween.stop(alienAsset, {
				tint: true
			});
		}
		alienAsset.tint = 0xff5252;
		self.hitTween = tween(alienAsset, {
			tint: 0x8d3abf
		}, {
			duration: 200,
			easing: tween.linear,
			onFinish: function onFinish() {
				self.hitTween = null;
			}
		});
	};
	// For movement
	self.speed = 12 + Math.random() * 3; // Stronger and faster
	self.update = function () {
		// Only move downwards, do not follow rocket's x position
		self.y += self.speed;
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x000000
});

/**** 
* Game Code
****/ 
// Life bar background
// Life bar
// Alien hit flash
// Bullet
// Alien (enemy)
// Rocket (player)
// Game constants
var GAME_WIDTH = 2048;
var GAME_HEIGHT = 2732;
// --- Starfield background ---
var stars = [];
var STAR_COUNT = 60;
for (var i = 0; i < STAR_COUNT; ++i) {
	var star = new Star();
	star.x = 10 + Math.random() * (GAME_WIDTH - 20);
	star.y = Math.random() * GAME_HEIGHT;
	stars.push(star);
	game.addChildAt(star, 0); // Add behind all other objects
}
var ROCKET_START_LIFE = 3;
var LEVEL_TO_BOSS = 7;
// Game state
var rocket = null;
var bullets = [];
var aliens = [];
var level = 1;
var rocketLife = ROCKET_START_LIFE;
var bulletPower = 1; // Bullet power, increases every level
var canShoot = true;
var shootCooldown = 0;
var dragNode = null;
var lastMoveX = 0;
var lastMoveY = 0;
var score = 0;
var bossSpawned = false;
var enemyBullets = []; // Track enemy bullets
// GUI elements
var scoreTxt = new Text2('0', {
	size: 90,
	fill: "#fff"
});
scoreTxt.anchor.set(0.5, 1);
// Ensure score is always visible
scoreTxt.alpha = 1;
scoreTxt.visible = true;
// Position the score text horizontally aligned with the rocket, above it
scoreTxt.x = GAME_WIDTH / 2;
scoreTxt.y = GAME_HEIGHT - 400 - (rocket ? rocket.height / 2 : 110) - 40; // 40px above rocket top, fallback if rocket not yet created
LK.gui.top.addChild(scoreTxt);
if (LK.gui.top.children && LK.gui.top.children.length > 1) {
	LK.gui.top.setChildIndex(scoreTxt, LK.gui.top.children.length - 1);
}
var lifeBarBg = LK.getAsset('lifeBarBg', {
	anchorX: 0.5,
	anchorY: 0.5,
	x: 0,
	y: 0
});
var lifeBar = LK.getAsset('lifeBar', {
	anchorX: 0,
	anchorY: 0.5,
	x: -200,
	y: 0
});
var lifeBarContainer = new Container();
lifeBarContainer.addChild(lifeBarBg);
lifeBarContainer.addChild(lifeBar);
lifeBarContainer.x = GAME_WIDTH / 2;
lifeBarContainer.y = 180;
LK.gui.top.addChild(lifeBarContainer);
// Level bar background and bar
// Small, horizontal level bar and level number to the right of the pause button in the GUI
var LEVEL_BAR_WIDTH = 220;
var LEVEL_BAR_HEIGHT = 22;
var levelBarBg = LK.getAsset('lifeBarBg', {
	anchorX: 0.0,
	// left align
	anchorY: 0.5,
	x: 0,
	y: 0,
	width: LEVEL_BAR_WIDTH,
	height: LEVEL_BAR_HEIGHT
});
var levelBar = LK.getAsset('lifeBar', {
	anchorX: 0.0,
	// left align
	anchorY: 0.5,
	x: 0,
	y: 0,
	width: 0,
	// Start empty, will be set by updateLevelBar
	height: LEVEL_BAR_HEIGHT
});
levelBar.tint = 0x1976d2; // blue for level bar
// Level number text
var levelTxt = new Text2('1', {
	size: 60,
	fill: "#fff"
});
levelTxt.anchor.set(0, 0.5); // left align, vertically centered
// Container for level bar and number
var levelBarContainer = new Container();
levelBarContainer.addChild(levelBarBg);
levelBarContainer.addChild(levelBar);
levelBarContainer.addChild(levelTxt);
// Position: right of pause button (pause is at top left, 0,0, so right of it, with margin)
levelBarContainer.x = 120; // 100px for pause + 20px margin
levelBarContainer.y = 60; // vertically centered with pause button
LK.gui.top.addChild(levelBarContainer);
// Helper to update life bar
function updateLifeBar() {
	var percent = rocketLife / ROCKET_START_LIFE;
	if (percent < 0) percent = 0;
	lifeBar.width = 400 * percent;
	if (percent > 0.5) {
		lifeBar.tint = 0x43a047;
	} else if (percent > 0.2) {
		lifeBar.tint = 0xffc107;
	} else {
		lifeBar.tint = 0xd32f2f;
	}
}
// Helper to update level bar
function updateLevelBar() {
	// Level progress: 0 to 1, based on kills in this level
	var killsThisLevel = score % 10;
	var percent = killsThisLevel / 10;
	if (percent < 0) percent = 0;
	if (percent > 1) percent = 1;
	levelBar.width = LEVEL_BAR_WIDTH * percent;
	// Color: blue if not full, green if full
	if (percent >= 1) {
		levelBar.tint = 0x43a047;
	} else {
		levelBar.tint = 0x1976d2;
	}
}
// Helper to update level text (show level number in GUI)
function updateLevelText() {
	if (typeof levelTxt !== "undefined") {
		levelTxt.setText("Lv " + level);
	}
}
// Helper to update score text
function updateScoreText() {
	scoreTxt.setText(score);
	updateLevelBar();
}
// Spawn a new alien
function spawnAlien() {
	var alien;
	if (level === LEVEL_TO_BOSS && !bossSpawned) {
		alien = new BossAlien();
		// Boss hp scales with level (optional, can be made harder)
		alien.hp = 6 + Math.floor((level - 1) * 1.5);
		bossSpawned = true;
	} else {
		// 30% chance to spawn a StrongAlien, 70% normal Alien
		if (Math.random() < 0.3 && level > 2) {
			alien = new StrongAlien();
			// StrongAlien hp increases with level
			alien.hp = 4 + Math.floor((level - 1) * 0.7);
		} else {
			alien = new Alien();
			// Alien hp increases with level
			alien.hp = 2 + Math.floor((level - 1) * 0.5);
		}
	}
	// Random x, but keep inside screen
	var margin = 120;
	alien.x = margin + Math.random() * (GAME_WIDTH - margin * 2);
	alien.y = -alien.height / 2;
	aliens.push(alien);
	game.addChild(alien);
}
// Reset game state
function resetGame() {
	// Remove all bullets and aliens
	for (var i = 0; i < bullets.length; ++i) {
		bullets[i].destroy();
	}
	for (var j = 0; j < aliens.length; ++j) {
		aliens[j].destroy();
	}
	for (var k = 0; k < enemyBullets.length; ++k) {
		enemyBullets[k].destroy();
	}
	bullets = [];
	aliens = [];
	enemyBullets = [];
	level = 1;
	rocketLife = ROCKET_START_LIFE;
	canShoot = true;
	shootCooldown = 0;
	dragNode = null;
	lastMoveX = 0;
	lastMoveY = 0;
	score = 0;
	bossSpawned = false;
	updateLevelText();
	updateScoreText();
	updateLifeBar();
	updateLevelBar();
}
// Initialize rocket
rocket = new Rocket();
rocket.x = GAME_WIDTH / 2;
rocket.y = GAME_HEIGHT - 400;
game.addChild(rocket);
// Move scoreTxt to be above the rocket, horizontally aligned
scoreTxt.x = rocket.x;
scoreTxt.y = rocket.y - rocket.height / 2 - 40; // 40px above rocket top
// Initial GUI
updateLevelText();
updateScoreText();
updateLifeBar();
updateLevelBar();
// Touch/move controls
game.down = function (x, y, obj) {
	// Only start drag if touch is on rocket
	var local = rocket.toLocal(game.toGlobal({
		x: x,
		y: y
	}));
	if (local.x > -rocket.width / 2 && local.x < rocket.width / 2 && local.y > -rocket.height / 2 && local.y < rocket.height / 2) {
		dragNode = rocket;
		lastMoveX = x;
		lastMoveY = y;
	}
};
game.move = function (x, y, obj) {
	// Always move the rocket to the mouse/touch position, clamped to screen
	var newX = x;
	var halfW = rocket.width / 2;
	if (newX < halfW) newX = halfW;
	if (newX > GAME_WIDTH - halfW) newX = GAME_WIDTH - halfW;
	rocket.x = newX;
	// Y position stays fixed at the starting Y
	rocket.y = GAME_HEIGHT - 400;
	lastMoveX = x;
	lastMoveY = y;
};
game.up = function (x, y, obj) {
	dragNode = null;
};
// Tap to shoot (left mouse button or tap)
game.down = function (x, y, obj) {
	// Only start drag if touch is on rocket
	var local = rocket.toLocal(game.toGlobal({
		x: x,
		y: y
	}));
	if (local.x > -rocket.width / 2 && local.x < rocket.width / 2 && local.y > -rocket.height / 2 && local.y < rocket.height / 2) {
		dragNode = rocket;
		lastMoveX = x;
		lastMoveY = y;
	}
	// Always allow shooting with left mouse button/tap, regardless of drag state
	if (canShoot) {
		shootBullet();
	}
};
// Shoot bullet
function shootBullet() {
	if (!canShoot) return;
	var bullet = new Bullet();
	bullet.x = rocket.x;
	bullet.y = rocket.y - rocket.height / 2 - 20;
	bullets.push(bullet);
	game.addChild(bullet);
	canShoot = false;
	shootCooldown = 10; // 10 ticks cooldown
}
// Main update loop
game.update = function () {
	// Shooting cooldown
	if (!canShoot) {
		shootCooldown--;
		if (shootCooldown <= 0) {
			canShoot = true;
		}
	}
	// Update stars
	for (var si = 0; si < stars.length; ++si) {
		stars[si].update();
	}
	// Keep score counter aligned with rocket
	scoreTxt.x = rocket.x;
	scoreTxt.y = rocket.y - rocket.height / 2 - 40; // 40px above rocket top
	// (level bar stays fixed in GUI, do not move with rocket)
	// Update bullets
	for (var i = bullets.length - 1; i >= 0; --i) {
		var b = bullets[i];
		b.update();
		// Remove if off screen
		if (b.y < -100) {
			b.destroy();
			bullets.splice(i, 1);
			continue;
		}
	}
	// Update aliens
	for (var j = aliens.length - 1; j >= 0; --j) {
		var a = aliens[j];
		a.update();
		// Remove if off screen
		if (a.y > GAME_HEIGHT + 200) {
			a.destroy();
			aliens.splice(j, 1);
			continue;
		}
		// Alien shooting logic: all aliens shoot every eligible tick (no randomness, no alignment check)
		if (level > 1 && a.y > 0 && a.y < GAME_HEIGHT - 400) {
			if (LK.ticks % Math.max(60 - level * 4, 18) === 0) {
				var enemyBullet = new EnemyBullet();
				enemyBullet.x = a.x;
				enemyBullet.y = a.y + a.height / 2 + 10;
				enemyBullets.push(enemyBullet);
				game.addChild(enemyBullet);
			}
		}
		// Check collision with rocket (alien-rocket contact)
		if (a.intersects(rocket)) {
			if (rocketLife > 0) {
				rocketLife--;
				updateLifeBar();
				rocket.flash();
			}
			// Remove alien on contact
			a.destroy();
			aliens.splice(j, 1);
			// Check for game over
			if (rocketLife <= 0) {
				LK.effects.flashScreen(0xff0000, 1000);
				LK.showGameOver();
				return;
			}
		}
		// No alien-rocket collision: aliens do not damage rocket by contact
	}
	// Update enemy bullets
	for (var eb = enemyBullets.length - 1; eb >= 0; --eb) {
		var ebull = enemyBullets[eb];
		ebull.update();
		// Remove if off screen
		if (ebull.y > GAME_HEIGHT + 100) {
			ebull.destroy();
			enemyBullets.splice(eb, 1);
			continue;
		}
		// Check collision with rocket
		if (ebull.intersects(rocket)) {
			if (rocketLife > 0) {
				rocketLife--;
				updateLifeBar();
				rocket.flash();
			}
			ebull.destroy();
			enemyBullets.splice(eb, 1);
			// Check for game over
			if (rocketLife <= 0) {
				LK.effects.flashScreen(0xff0000, 1000);
				LK.showGameOver();
				return;
			}
		}
	}
	// Bullet-alien collisions
	for (var i2 = bullets.length - 1; i2 >= 0; --i2) {
		var b2 = bullets[i2];
		for (var j2 = aliens.length - 1; j2 >= 0; --j2) {
			var a2 = aliens[j2];
			if (b2.intersects(a2)) {
				a2.hp -= b2.power !== undefined ? b2.power : 1; // Use bullet power, fallback to 1
				a2.flash();
				b2.destroy();
				bullets.splice(i2, 1);
				if (a2.hp <= 0) {
					a2.destroy();
					aliens.splice(j2, 1);
					score++;
					updateScoreText();
					// Increase level every 10 kills
					if (level < LEVEL_TO_BOSS && score % 10 === 0) {
						level++;
						bulletPower++; // Increase bullet power each level
						updateLevelText();
						// Star explosion effect at center of screen
						for (var sx = 0; sx < 18; ++sx) {
							(function (sx) {
								var star = new Star();
								star.x = GAME_WIDTH / 2;
								star.y = GAME_HEIGHT / 2;
								// Give each star a random direction and speed
								var angle = Math.PI * 2 * (sx / 18);
								var speed = 18 + Math.random() * 12;
								var vx = Math.cos(angle) * speed;
								var vy = Math.sin(angle) * speed;
								var life = 32 + Math.floor(Math.random() * 16);
								var tick = 0;
								// Animate star outward and fade out
								star.update = function () {
									star.x += vx;
									star.y += vy;
									star.alpha -= 0.025;
									tick++;
									if (tick > life || star.alpha <= 0) {
										star.destroy();
									}
								};
								game.addChild(star);
							})(sx);
						}
						// Change all background star colors
						var colorChoices = [0xffffff, 0xe3f2fd, 0xfffde7, 0xb3e5fc, 0xfff9c4, 0xffb3c6, 0xc5e1a5, 0xffcc80, 0x90caf9, 0xf8bbd0];
						for (var sc = 0; sc < stars.length; ++sc) {
							var starObj = stars[sc];
							// Only change tint if starObj has children and a valid asset
							if (starObj.children && starObj.children.length > 0 && starObj.children[0]) {
								var newColor = colorChoices[Math.floor(Math.random() * colorChoices.length)];
								starObj.children[0].tint = newColor;
							}
						}
						// Change background color on every level up (only black and gray tones)
						var bgGrayColors = [0x000000,
						// black
						0x111111,
						// very dark gray
						0x222222,
						// dark gray
						0x333333,
						// gray
						0x444444,
						// medium gray
						0x555555,
						// medium gray
						0x666666,
						// lighter gray
						0x777777,
						// light gray
						0x888888,
						// lighter gray
						0x999999,
						// even lighter gray
						0xaaaaaa,
						// pale gray
						0xbbbbbb,
						// pale gray
						0xcccccc,
						// very pale gray
						0xdddddd,
						// near white
						0x22282a // blueish dark gray for variety but still grayish
						];
						var newBgColor = bgGrayColors[Math.floor(Math.random() * bgGrayColors.length)];
						game.setBackgroundColor(newBgColor);
					}
					// If boss defeated, win
					if (level === LEVEL_TO_BOSS && bossSpawned && aliens.length === 0) {
						LK.effects.flashScreen(0x00e676, 1000);
						LK.showYouWin();
						return;
					}
				}
				break;
			}
		}
	}
	// Alien spawn logic
	if (level < LEVEL_TO_BOSS) {
		// Increase max aliens on screen as level increases
		var maxAliens = 2 + Math.floor((level - 1) / 2); // +1 every 2 levels (2,3,4,5...)
		if (aliens.length < maxAliens && LK.ticks % (60 - level * 4) === 0) {
			spawnAlien();
		}
	} else if (level === LEVEL_TO_BOSS && !bossSpawned) {
		// Spawn boss
		spawnAlien();
	}
};
// Initial spawn
spawnAlien();

===================================================================
--- original.js
+++ change.js
@@ -644,11 +644,40 @@
 								var newColor = colorChoices[Math.floor(Math.random() * colorChoices.length)];
 								starObj.children[0].tint = newColor;
 							}
 						}
-						// Change background color on every level up
-						var bgColors = [0x000000, 0x0d133d, 0x1a237e, 0x263238, 0x004d40, 0x311b92, 0x880e4f, 0x212121, 0x37474f, 0x263238, 0x1565c0, 0x4a148c, 0x827717, 0x00695c, 0x01579b];
-						var newBgColor = bgColors[Math.floor(Math.random() * bgColors.length)];
+						// Change background color on every level up (only black and gray tones)
+						var bgGrayColors = [0x000000,
+						// black
+						0x111111,
+						// very dark gray
+						0x222222,
+						// dark gray
+						0x333333,
+						// gray
+						0x444444,
+						// medium gray
+						0x555555,
+						// medium gray
+						0x666666,
+						// lighter gray
+						0x777777,
+						// light gray
+						0x888888,
+						// lighter gray
+						0x999999,
+						// even lighter gray
+						0xaaaaaa,
+						// pale gray
+						0xbbbbbb,
+						// pale gray
+						0xcccccc,
+						// very pale gray
+						0xdddddd,
+						// near white
+						0x22282a // blueish dark gray for variety but still grayish
+						];
+						var newBgColor = bgGrayColors[Math.floor(Math.random() * bgGrayColors.length)];
 						game.setBackgroundColor(newBgColor);
 					}
 					// If boss defeated, win
 					if (level === LEVEL_TO_BOSS && bossSpawned && aliens.length === 0) {