===================================================================
--- original.js
+++ change.js
@@ -1,6 +1,238 @@
-/****
+/**** 
+* Plugins
+****/ 
+var tween = LK.import("@upit/tween.v1");
+
+/**** 
+* Classes
+****/ 
+// Light class: represents a single light (red or green)
+var StartLight = Container.expand(function () {
+	var self = Container.call(this);
+	// By default, start as "off" (invisible)
+	self.state = 'off'; // 'off', 'red', 'green'
+	self.lightAsset = null;
+	// Set state: 'off', 'red', 'green'
+	self.setState = function (state) {
+		if (self.lightAsset) {
+			self.removeChild(self.lightAsset);
+			self.lightAsset = null;
+		}
+		self.state = state;
+		if (state === 'red') {
+			self.lightAsset = self.attachAsset('redLight', {
+				anchorX: 0.5,
+				anchorY: 0.5
+			});
+			self.lightAsset.alpha = 1;
+		} else if (state === 'green') {
+			self.lightAsset = self.attachAsset('greenLight', {
+				anchorX: 0.5,
+				anchorY: 0.5
+			});
+			self.lightAsset.alpha = 1;
+		}
+		// else: off, do not show anything
+	};
+	// Flash effect for green
+	self.flashGreen = function () {
+		if (self.state === 'green' && self.lightAsset) {
+			self.lightAsset.alpha = 0.5;
+			tween(self.lightAsset, {
+				alpha: 1
+			}, {
+				duration: 200,
+				easing: tween.easeOut
+			});
+		}
+	};
+	return self;
+});
+
+/**** 
 * Initialize Game
-****/
+****/ 
 var game = new LK.Game({
-	backgroundColor: 0x000000
-});
\ No newline at end of file
+	backgroundColor: 0x181818
+});
+
+/**** 
+* Game Code
+****/ 
+// We'll use tween for light animations
+// Green light asset
+// Red light asset
+// We'll use shapes for the lights
+// 5 red lights (circles), 1 green light (circle), warning text, result text
+// --- Layout constants ---
+var NUM_LIGHTS = 5;
+var LIGHT_SPACING = 260; // px between lights
+var LIGHT_Y = 900; // vertical position of lights
+var LIGHT_START_X = (2048 - (NUM_LIGHTS - 1) * LIGHT_SPACING) / 2; // center the row
+// --- State variables ---
+var lights = [];
+var currentPhase = 'idle'; // 'idle', 'lights', 'waitGreen', 'green', 'result', 'falseStart'
+var lightIndex = 0;
+var timers = [];
+var greenTimestamp = 0;
+var tapTimestamp = 0;
+var resultText = null;
+var warningText = null;
+var instructionText = null;
+// --- GUI elements ---
+var guiResultText = null;
+// --- Helper functions ---
+function clearTimers() {
+	for (var i = 0; i < timers.length; ++i) {
+		LK.clearTimeout(timers[i]);
+	}
+	timers = [];
+}
+function resetLights() {
+	for (var i = 0; i < lights.length; ++i) {
+		lights[i].setState('off');
+	}
+}
+function showInstruction(msg) {
+	if (!instructionText) {
+		instructionText = new Text2(msg, {
+			size: 90,
+			fill: 0xFFFFFF
+		});
+		instructionText.anchor.set(0.5, 0);
+		LK.gui.top.addChild(instructionText);
+		instructionText.y = 180;
+	}
+	instructionText.setText(msg);
+	instructionText.visible = true;
+}
+function hideInstruction() {
+	if (instructionText) instructionText.visible = false;
+}
+function showWarning(msg) {
+	if (!warningText) {
+		warningText = new Text2(msg, {
+			size: 120,
+			fill: 0xFF4444
+		});
+		warningText.anchor.set(0.5, 0.5);
+		LK.gui.center.addChild(warningText);
+	}
+	warningText.setText(msg);
+	warningText.visible = true;
+}
+function hideWarning() {
+	if (warningText) warningText.visible = false;
+}
+function showResult(msg) {
+	if (!resultText) {
+		resultText = new Text2(msg, {
+			size: 120,
+			fill: 0x22FF22
+		});
+		resultText.anchor.set(0.5, 0.5);
+		LK.gui.center.addChild(resultText);
+	}
+	resultText.setText(msg);
+	resultText.visible = true;
+}
+function hideResult() {
+	if (resultText) resultText.visible = false;
+}
+// --- Game logic ---
+function startSequence() {
+	clearTimers();
+	resetLights();
+	hideWarning();
+	hideResult();
+	showInstruction("Wait for green, then tap as fast as you can!");
+	currentPhase = 'lights';
+	lightIndex = 0;
+	// Start lighting up the reds, one by one
+	timers.push(LK.setTimeout(lightNext, 700));
+}
+function lightNext() {
+	if (lightIndex < NUM_LIGHTS) {
+		lights[lightIndex].setState('red');
+		lightIndex += 1;
+		timers.push(LK.setTimeout(lightNext, 700));
+	} else {
+		// All reds are on, now wait random time before green
+		currentPhase = 'waitGreen';
+		// Random delay: 0.7s to 2.2s
+		var delay = 700 + Math.floor(Math.random() * 1500);
+		timers.push(LK.setTimeout(showGreen, delay));
+	}
+}
+function showGreen() {
+	// All lights turn green
+	for (var i = 0; i < lights.length; ++i) {
+		lights[i].setState('green');
+		lights[i].flashGreen();
+	}
+	currentPhase = 'green';
+	greenTimestamp = Date.now();
+	showInstruction("GO!");
+}
+function handleTap() {
+	if (currentPhase === 'idle' || currentPhase === 'result' || currentPhase === 'falseStart') {
+		// Start new round
+		startSequence();
+		return;
+	}
+	if (currentPhase === 'lights' || currentPhase === 'waitGreen') {
+		// False start!
+		clearTimers();
+		currentPhase = 'falseStart';
+		hideInstruction();
+		showWarning("False Start!\nTap to try again");
+		resetLights();
+		return;
+	}
+	if (currentPhase === 'green') {
+		tapTimestamp = Date.now();
+		var reaction = tapTimestamp - greenTimestamp;
+		currentPhase = 'result';
+		hideInstruction();
+		showResult("Reaction Time:\n" + formatReaction(reaction) + "\n\nTap to try again");
+		resetLights();
+		return;
+	}
+}
+function formatReaction(ms) {
+	var s = Math.floor(ms / 1000);
+	var msPart = ms % 1000;
+	var str = '';
+	if (s > 0) {
+		str += s + '.';
+		if (msPart < 100) str += '0';
+		if (msPart < 10) str += '0';
+		str += msPart;
+		str += " s";
+	} else {
+		str += msPart + " ms";
+	}
+	return str;
+}
+// --- Setup lights ---
+for (var i = 0; i < NUM_LIGHTS; ++i) {
+	var light = new StartLight();
+	light.x = LIGHT_START_X + i * LIGHT_SPACING;
+	light.y = LIGHT_Y;
+	light.setState('off');
+	game.addChild(light);
+	lights.push(light);
+}
+// --- Setup instruction text ---
+showInstruction("Tap to start!");
+// --- Input handling ---
+game.down = function (x, y, obj) {
+	handleTap();
+};
+// --- Clean up on game over (not needed, but for completeness) ---
+game.destroy = function () {
+	clearTimers();
+};
+// --- Start in idle state ---
+currentPhase = 'idle';
+// --- No update loop needed ---
\ No newline at end of file