Domino Rally

Let me understand the task: I need to make a brand new game that hasn't been done before and is useful to the audience. Let me first check what games already exist in the arcade to avoid repetition, then come up with a fresh game idea.

Let me start by installing the shell tools and checking the existing games.

Let me see the full list and also check the index to understand what kinds of games exist.

Let me look at the game descriptions in the index to understand what types of games exist, so I can create something truly new and different.

Let me look at the descriptions of the games to understand what's been done. Let me extract the game descriptions from the index.

Now I have a good picture of the 87 existing games. Let me think about what would be a fresh, innovative game that hasn't been done before.

Looking at the existing games, I see:

• Puzzle games: 2048, Sudoku, Picross, Hashi, Mastermind, Box Pusher, Tower of Hanoi, Knot Free, Logic Lab
• Action/Arcade: Snake, Neon Breakout, Stellar Pinball, Type Storm, Nova Pop
• Strategy: Battleship, Nexus Defense, Realm Guard, Transit Link
• Physics: Gravity Golf, Gravity Wells, Lunar Lander, Powder Lab
• Creative/Art: Pixel Painter, Inkflow, Stained Glass Studio, Bonsai Zen, Harmonograph
• Music/Rhythm: Beat Drop, Pulse, Harmony Grid
• Word/Language: Word Forge, Word Hunt, Code Quest, Cipher Master, Dot Dash
• Science/STEM: DNA Sequencer, Quantum Circuit, Constellation Cartographer, Biome Builder
• Simulation: Stock Tycoon, Terraform, Reef Keeper, Lighthouse Keeper
• Card/Board: Dungeon Deck, Mancala
• Other: Shadow Play, Safecracker, Magnetar, etc.

I need something truly different. Let me think about game concepts that are:

1. Not represented in the existing collection
2. Useful/educational/entertaining
3. Mechanically distinct
4. Visually distinct

Ideas:

1. Origami Folder - A game where you fold paper to create shapes. But this might be complex.
2. Lock Picker - Already have Safecracker.
3. Juggling Simulator - A rhythm/timing game about juggling.
4. Kaleidoscope - An interactive art toy.
5. Weather Simulator - Control weather patterns.
6. Ant Colony - Simulation of ant behavior.
7. Music Composer - Already have Harmony Grid, Beat Drop.
8. Tensegrity Builder - Build structures with tension/compression.
9. Origami - Fold paper.
10. Pendulum Painter - Already have Harmonograph.
11. Fruit Slice - Already have similar action games.
12. Plumber/Pipe - Already have Neon Flow.
13. Domino Effect - Set up dominoes and knock them down.
14. Rube Goldberg Machine - Build complex machines.
15. Tensegrity - Build structures.
16. Flocking/Boids - Already have Murmuration.
17. Cellular Automata - Already have Mycelium.
18. Tangram - Already have Tangram Quest.
19. Nonogram - Already have Picross Quest.
20. Sokoban - Already have Box Pusher.
21. Maze - Already have Echo Maze.
22. Tower Defense - Already have Nexus Defense.
23. Idle/Incremental - Already have Cosmic Forge.
24. Roguelike - Already have Dungeon Delver.
25. Fishing Game - Already have Deep Cast.
26. Cooking Game - Not done! A cooking/recipe game.
27. Gardening Game - Not done explicitly (Terraform is about planets).
28. Origami - Not done.
29. Knot Tying - Already have Knot Free.
30. Music Sequencer - Already have Harmony Grid.
31. Drum Machine - Already have Beat Drop.
32. Color Theory - Already have Chroma Shift, Color Clash.
33. Optical Illusion - Not done!
34. Perspective Puzzle - Not done!
35. Shadow/Light - Already have Shadow Play, Lumen.
36. Origami - Not done.
37. Folding - Not done.
38. Domino - Not done.
39. Rube Goldberg - Not done.
40. Marble Run - Not done! A marble run / marble machine builder.
41. Plinko - Not done explicitly.
42. Garden/Plant growing - Not done explicitly.
43. Bonsai - Already have Bonsai Zen.
44. Terrarium - Not done.
45. Aquarium - Already have Tide Pool, Reef Keeper.
46. Bee/Honey - Already have Hive.
47. Origami - Not done.
48. Paper airplane - Already have Paper Wings.
49. Kite flying - Not done.
50. Wind/Weather - Not done.

Let me think about what would be genuinely interesting, useful, and novel:

Idea: "Domino Rally" - A domino chain reaction game where you place dominoes on a grid and then trigger them to fall, creating chain reactions to hit targets. This combines physics, puzzle-solving, and creativity. It's visually satisfying and mechanically distinct from anything in the collection.

Actually, let me think more carefully. Let me consider:

Idea: "Marble Run" / "Marble Machine" - A physics-based marble run builder where you place tracks, ramps, loops, and obstacles to guide a marble from start to finish. This is creative, physics-based, and visually engaging.

But wait - do I have a physics engine? I'd need to implement basic physics. That could be complex but doable with simple 2D physics.

Idea: "Origami Studio" - An interactive origami game where you fold virtual paper to match target shapes. This would use SVG or Canvas transforms. Very creative and unique.

Idea: "Kaleidoscope" - An interactive kaleidoscope toy where you draw in one segment and it mirrors across multiple axes. Very visual, creative, and meditative.

Idea: "Domino Cascade" - Place dominoes and watch them fall in chain reactions. Physics-based puzzle.

Idea: "Pendulum Wave" - Not really a game.

Idea: "Circuit Scramble" - Already have Circuit Breaker, Quantum Circuit.

Idea: "Locksmith" - Already have Safecracker.

Idea: "Weather Master" - Control weather systems.

Idea: "Origami" - Let me go with this. It's unique, creative, educational, and visually distinct.

Actually, let me think about what's truly novel and engaging:

Idea: "Domino Rally" - This is a great concept. You place dominoes on a 2D grid, set up a starting push, and watch them cascade. The goal is to hit all target markers. It's a physics puzzle with chain reactions. Very satisfying to watch.

But implementing realistic domino physics in 2D is actually quite involved. Let me think of something more achievable but still impressive.

Idea: "Constellation" - Already have Constellation Cartographer.

Idea: "Star Map" - Already have that.

Idea: "Origami" - Let me think about this more. An origami game where you fold paper step by step to create shapes. The challenge is matching the target shape. This could be done with SVG transforms.

Actually, let me think about a different approach. What about a game that's both fun and educational?

Idea: "Chemistry Lab" / "Element Mixer" - Combine elements to discover compounds. But we have Alchemy Lab already.

Idea: "Periodic Table" - An educational game about the periodic table.

Idea: "Music Theory" - Already have music games.

Idea: "Geography/Map" - A game about identifying countries or capitals.

Idea: "Typing" - Already have Type Storm.

Idea: "Memory/Concentration" - A memory matching game. Classic but not in the collection!

Wait, let me check... I don't see a memory/concentration card matching game in the list. But that's pretty basic.

Idea: "Simon Says" - A pattern memory game. We have Pulse which might be similar.

Idea: "Reaction Time" - Already have Reaction Chain.

Let me think about what would be genuinely fresh and engaging...

Idea: "Domino Rally" - I keep coming back to this. Let me think about how to implement it.

Actually, you know what would be really cool and unique? A "Rube Goldberg Machine Builder" - where you place various mechanical elements (ramps, seesaws, dominoes, balls, pulleys, fans, etc.) on a canvas to create a chain reaction that achieves a goal (like getting a ball into a bucket). This is creative, physics-based, puzzle-solving, and visually satisfying.

But implementing a full physics engine is complex. Let me think about a simpler but still engaging approach.

Idea: "Marble Drop" - A Plinko-style game where you drop marbles through a field of pegs, but with the ability to place/rotate pegs to guide marbles to targets. Simpler physics (just gravity + bouncing) but still engaging.

Actually, let me think about what's truly novel...

Idea: "Origami Fold" - I think this is the most unique. Let me design it:

The game presents a piece of paper (represented as a polygon in SVG or Canvas). The player can make fold lines and fold the paper along those lines. The goal is to match a target shape. Each level gives you a target silhouette and you need to fold the paper to match it.

This is:

• Visually unique (paper folding aesthetic)
• Mechanically novel (folding mechanics)
• Educational (spatial reasoning, geometry)
• Satisfying and meditative

But implementing realistic paper folding is quite complex mathematically.

Let me think of something more achievable...

Idea: "Kaleidoscope Painter" - An interactive kaleidoscope where you draw with your mouse and the drawing is mirrored across N axes of symmetry. You can change the number of segments, colors, brush sizes. It's creative, meditative, and visually stunning. This is achievable and unique.

But is it a "game"? It's more of a creative toy. Let me add game elements - like challenges to recreate specific patterns, or a "match the target" mode.

Actually, let me think about what would be both fun AND useful...

Idea: "Domino Rally" - Let me go with a simplified version. Instead of full physics, I can use a grid-based system where dominoes are placed on a grid, and when triggered, they fall in a chain reaction. The direction of fall is determined by placement. The goal is to create a chain that hits all targets.

This is:

• Puzzle-based (planning the chain)
• Visually satisfying (watching dominoes fall)
• Mechanically simple but strategically deep
• Unique in the collection

Let me design this:

Domino Rally

• Grid-based playfield
• Place dominoes on grid cells, each with a direction (N/S/E/W)
• When you trigger the first domino, it falls in its direction, knocking over the next domino in its path
• Chain reactions spread
• Goal: hit all target markers with the chain
• Obstacles: walls, gaps, special tiles
• Multiple levels with increasing complexity

Actually, this is essentially a path-finding/chain-reaction puzzle. Let me think about whether this is too similar to existing games...

Looking at the list: Reaction Chain might be similar. Let me think about what Reaction Chain is... probably a chemistry-style chain reaction game.

Let me go with something different. How about:

Idea: "Tensegrity Builder" - Build structures using tension and compression. Too complex.

Idea: "Pendulum Painter" - Already have Harmonograph.

Idea: "Sand Timer" - A game about timing.

Idea: "Windmill" - A game about wind power.

OK, let me take a step back and think about what genres are NOT represented:

1. Rhythm/Music - Have Beat Drop, Harmony Grid, Pulse
2. Puzzle - Many
3. Action - Many
4. Strategy - Several
5. Simulation - Several
6. Creative/Art - Several
7. Educational - Several
8. Physics - Several
9. Card/Board - A few
10. Word - Several
11. Memory - Maybe not explicitly?
12. Stealth - Not represented!
13. Racing - Not represented!
14. Sports - Not represented!
15. Cooking - Not represented!
16. Gardening - Not represented!
17. Farming - Not represented!
18. Crafting - Have Forge Master, Cosmic Forge
19. Detective/Mystery - Not represented!
20. Horror - Not represented (but maybe not appropriate)
21. Dating Sim - Not represented (but maybe not appropriate)
22. Idle/Incremental - Have Cosmic Forge
23. Roguelike - Have Dungeon Delver
24. Tower Defense - Have Nexus Defense
25. Maze - Have Echo Maze
26. Platformer - Not explicitly represented!
27. Shooter - Not explicitly represented!
28. Fighting - Not represented!
29. Racing - Not represented!

Hmm, a racing game or platformer could be interesting. But those are pretty standard. Let me think about something more unique.

Idea: "Domino Rally" - I keep coming back to this. Let me just go with it but make it really polished.

Actually, wait. Let me think about a completely different concept:

Idea: "Origami Studio" - An interactive paper folding game. The player starts with a square piece of paper and can fold it along lines they draw. The goal is to match target shapes. This is unique, creative, and educational.

But the math of paper folding is complex. Let me think about a simplified version...

Actually, let me think about what would be genuinely fun and novel:

Idea: "Kaleidoscope" - A creative toy/game where you draw in a wedge and it's mirrored around a center point. You can:

• Adjust the number of mirror segments (2-16)
• Choose colors and brush sizes
• Draw freely
• Try to match target patterns in challenge mode
• Save/export your creation

This is:

• Visually stunning
• Creative and meditative
• Educational (symmetry, geometry)
• Unique in the collection
• Achievable with Canvas

Let me go with this! A kaleidoscope drawing game with both free-play and challenge modes.

Actually, wait. Let me reconsider. The task says "something that is useful to the audience." A kaleidoscope is more of a toy than a game. Let me think about what's both fun and useful...

Idea: "Domino Rally" - A puzzle game where you place dominoes to create chain reactions. This is:

• Fun and satisfying
• Educational (planning, cause and effect, physics)
• Unique
• A proper game with levels and goals

Let me go with Domino Rally. Here's my design:

Domino Rally

• Grid-based playfield (e.g., 12x8)
• Player places dominoes on grid cells
• Each domino has a direction (up/down/left/right)
• Click "Start" to trigger the chain reaction
• Dominoes fall in sequence, knocking over adjacent dominoes
• Goal: knock over all target tiles
• Constraints: limited number of dominoes, walls/obstacles, gaps
• Multiple levels with increasing difficulty
• Visual: satisfying domino falling animation
• Audio: clicking sounds as dominoes fall

Actually, I realize this might be too similar to "Reaction Chain" which is already in the collection. Let me check what that game is about.

Let me look at a few existing games to understand what they do, so I can ensure my new game is distinct.

Actually, let me just go with a completely different concept. Let me think about what's truly novel...

Idea: "Constellation Weaver" - No, already have Constellation Cartographer and Starweave.

Idea: "Origami" - Let me try a simplified version. Instead of full 3D paper folding, I can do a 2D version where you fold a paper along horizontal/vertical/diagonal lines, and the paper transforms. The goal is to match a target shape.

Actually, this is getting too complex. Let me think of something achievable but impressive.

Idea: "Marble Maze" - Tilt-based marble maze. But we have Echo Maze.

Idea: "Labyrinth" - The classic wooden labyrinth game where you tilt the board to guide a marble through a maze, avoiding holes. This is:

• Classic and well-known
• Physics-based (tilt, gravity, momentum)
• Visually distinct (wooden board aesthetic)
• Fun and challenging
• Not explicitly in the collection (Echo Maze might be different)

Wait, but this requires tilt controls which on desktop would be arrow keys. And it's a fairly standard game. Let me think of something more unique.

Idea: "Domino Rally" - OK, I'll go with this but make it really polished and unique. Let me check if Reaction Chain is similar first.

Actually, let me just look at a couple of game descriptions to understand the landscape better, then decide.

Let me look at the index HTML more carefully to see game descriptions.

Now I have a comprehensive view of all 87 games. Let me think about what's NOT represented:

Looking at the collection, I see:

• Logic puzzles (many)
• Physics games (several)
• Creative/art games (several)
• Educational games (many)
• Strategy games (several)
• Simulation games (several)
• Music/rhythm games (several)
• Word games (several)
• Card/board games (a few)
• Action/arcade games (several)

What's NOT represented or could be done differently:

1. Domino chain reaction - Reaction Chain is about placing nodes with blast radius, not dominoes
2. Origami/paper folding - Not done (Paper Wings is about flying a paper airplane, not folding)
3. Kaleidoscope - Not done
4. Racing - Not done
5. Platformer - Not done
6. Stealth - Not done
7. Sports - Not done
8. Detective/mystery - Not done
9. Juggling - Not done
10. Pendulum/clock - Clockwork is about gears, not pendulums
11. Spinning top/beyblade - Not done
12. Domino - Not done
13. Marble run - Not done
14. Rube Goldberg - Not done
15. Pachinko - Not done
16. Pinball - Have Stellar Pinball
17. Plumber/pipes - Have Neon Flow
18. Tetris - Have Block Cascade
19. Match-3 - Have Gem Cascade
20. Sudoku - Have Sudoku Sage
21. Nonogram - Have Picross Quest
22. Sokoban - Have Box Pusher
23. Maze - Have Echo Maze
24. Tower defense - Have Nexus Defense
25. Idle/incremental - Have Cosmic Forge
26. Roguelike - Have Dungeon Delver
27. Deck builder - Have Dungeon Deck
28. Fishing - Have Deep Cast
29. Cooking - Have Sizzle (food truck)
30. Blacksmith - Have Forge Master
31. Farming/gardening - Not explicitly done
32. Weather - Not done
33. Photography - Not done
34. Music - Have several
35. Astronomy - Have Constellation Cartographer
36. Biology - Have DNA Sequencer, Mycelium, Reef Keeper, Tide Pool
37. Chemistry - Have Alchemy Lab
38. Physics - Have several
39. Electronics - Have Circuit Breaker, Quantum Circuit, Synapse
40. Math - Have Math Blitz
41. Cryptography - Have Cipher Master
42. Morse code - Have Dot Dash
43. Programming - Have Code Quest
44. Color theory - Have Chroma Shift, Prism, Lumen
45. Optics - Have Prism, Lumen, Photon Path
46. Magnetism - Have Magnetar
47. Gravity - Have Gravity Golf, Gravity Wells
48. Ecosystem - Have Biome Builder, Tide Pool, Reef Keeper
49. Terrarium - Not done
50. Bonsai - Have Bonsai Zen
51. Calligraphy - Have Inkflow
52. Pixel art - Have Pixel Painter
53. Stained glass - Have Stained Glass Studio
54. Fireworks - Have Pyrotechnia
55. Shadow - Have Shadow Play
56. Tangram - Have Tangram Quest
57. Origami - Not done!
58. Kaleidoscope - Not done!
59. Domino - Not done!
60. Marble run - Not done!
61. Rube Goldberg - Not done!
62. Pachinko - Not done!
63. Juggling - Not done!
64. Spinning top - Not done!
65. Weather - Not done!
66. Photography - Not done!
67. Detective - Not done!
68. Stealth - Not done!
69. Racing - Not done!
70. Platformer - Not done!
71. Sports - Not done!
72. Farming - Not done!
73. Terrarium - Not done!

OK, so there are many things not done. Let me pick something that's:

1. Genuinely novel and interesting
2. Achievable with good quality
3. Visually distinct
4. Mechanically engaging
5. Useful/educational

I'm going to go with "Domino Rally" - a domino chain reaction puzzle game. Here's why:

• It's NOT in the collection (Reaction Chain is about blast radius nodes, not dominoes)
• It's visually satisfying (watching dominoes fall)
• It's mechanically engaging (planning chain reactions)
• It's educational (cause and effect, spatial planning, physics)
• It's achievable with good quality
• It can have a unique visual style

Wait, actually, let me reconsider. Let me think about what would be truly impressive and unique...

Idea: "Kaleidoscope" - An interactive kaleidoscope drawing tool with challenge modes. This would be:

• Visually stunning (symmetric patterns)
• Creative and meditative
• Educational (symmetry, geometry)
• Unique in the collection
• Achievable with Canvas

But is it a "game"? I could add challenge modes where you need to recreate target patterns.

Actually, let me think about something more game-like...

Idea: "Domino Rally" - Let me go with this. It's a proper game with levels, goals, and satisfying gameplay.

Actually, you know what, let me think about something even more unique and interesting:

Idea: "Origami Studio" - A paper folding game where you fold virtual paper to match target shapes. This is:

• Genuinely novel (not in the collection)
• Educational (geometry, spatial reasoning)
• Visually unique (paper folding aesthetic)
• Mechanically interesting
• Useful (teaches spatial reasoning)

But implementing realistic paper folding is complex. Let me think about a simplified version...

Actually, let me go with something I can execute really well. Let me think about what would be both unique and achievable:

Idea: "Domino Rally" - A domino chain reaction puzzle. Here's my detailed design:

Concept: Place dominoes on a grid to create chain reactions that knock over all target tiles.

Mechanics:

• Grid-based playfield (e.g., 10x8)
• Player places dominoes on grid cells
• Each domino can be oriented in 4 directions (N, S, E, W)
• Click "Start" to push the first domino
• Dominoes fall in sequence, each knocking over the next domino in its direction
• Goal: knock over all target tiles
• Limited dominoes per level
• Obstacles: walls, gaps
• Special tiles: boosters (make dominoes fall faster), splitters (split the chain)

Visual Style: Warm, cozy aesthetic with wooden dominoes on a table surface. Or maybe a neon/cyberpunk style? Let me go with something unique - a warm, cozy, tabletop aesthetic with realistic-looking dominoes.

Actually, wait. Let me think about this differently. The domino falling mechanic is essentially a path-finding puzzle. You need to create a path from the start to all targets using dominoes. This is similar to pipe-connecting games (Neon Flow) or path-finding puzzles.

Let me think about what makes dominoes unique:

1. The visual satisfaction of watching them fall
2. The timing element (dominoes fall in sequence, not all at once)
3. The directionality (each domino falls in a specific direction)
4. Chain reactions (one domino knocks over the next)

OK, I think this is a good concept. But let me think about whether there's something even more interesting...

Idea: "Marble Run" - A physics-based marble run builder. Place tracks, ramps, and obstacles to guide a marble from start to finish. This is:

• Creative and physics-based
• Visually satisfying
• Unique in the collection
• Educational (physics, gravity, momentum)

But implementing a physics engine is complex. Let me think about a simpler version...

Actually, let me go with something completely different and unique:

Idea: "Kaleidoscope" - An interactive kaleidoscope with both creative and challenge modes. Here's my design:

Concept: A kaleidoscope drawing tool where your input is mirrored across multiple axes of symmetry.

Modes:

1. Free Play: Draw freely with various brushes, colors, and symmetry settings
2. Challenge Mode: Recreate target patterns by drawing in the kaleidoscope
3. Mandala Mode: Create mandala-like patterns with guided symmetry

Features:

• Adjustable symmetry (2-16 fold)
• Multiple brush types (solid, gradient, sparkle, glow)
• Color palette with HSL color picker
• Undo/redo
• Save/export as PNG
• Background patterns
• Particle effects
• Ambient sound

Visual Style: Rich, colorful, psychedelic with glowing trails and particle effects.

Hmm, but this is more of a creative tool than a game. Let me add more game elements...

Actually, let me think about what would be a really good, engaging GAME that's also unique...

Idea: "Domino Rally" - I keep coming back to this. Let me just commit to it and make it great.

Actually, wait. Let me think about one more idea:

Idea: "Pendulum Painter" - Already have Harmonograph.

Idea: "Spinning Top Arena" - A game where you control a spinning top in an arena, battling other tops. Physics-based combat. This is:

• Action-packed
• Physics-based
• Unique
• Fun

But implementing spinning top physics is complex.

Idea: "Juggle Master" - A juggling game where you keep balls in the air. Timing-based. This is:

• Simple but addictive
• Timing-based
• Unique
• Achievable

But it might be too simple.

OK, let me make a decision. I'll go with "Domino Rally" - a domino chain reaction puzzle game. It's:

1. Not in the collection
2. Visually satisfying
3. Mechanically engaging
4. Educational
5. Achievable with good quality
6. Has depth (multiple levels, increasing complexity)

Let me design it in detail:

Domino Rally

Core Mechanic: Place dominoes on a grid, orient them, and trigger a chain reaction to knock over all targets.

Grid: 12x8 grid (or variable per level)

Domino Types:

1. Standard Domino: Falls in the direction it's oriented, knocks over the next domino in its path
2. Splitter Domino: When it falls, it sends the chain in two directions (left and right of its fall direction)
3. Booster Domino: Makes the chain "jump" over a gap

Tile Types:

1. Empty: Can place dominoes here
2. Wall: Cannot place dominoes, blocks the chain
3. Target: Must be knocked over to win
4. Start: The first domino that gets pushed
5. Gap: Dominoes can't be placed here, and the chain stops unless a booster is used

Gameplay:

1. Player places dominoes on the grid
2. Each domino has a direction (click to rotate)
3. Click "Start" to trigger the chain
4. Watch dominoes fall in sequence
5. If all targets are knocked over, level complete
6. Star ratings based on domino efficiency (fewer dominoes = more stars)

Visual Style: I'll go with a warm, cozy, tabletop aesthetic. Wooden table background, realistic-looking dominoes with dots, warm lighting. Or maybe a more modern, clean aesthetic with colorful dominoes on a dark background.

Actually, let me go with a unique visual style - a retro arcade style with neon dominoes on a dark grid. This would be visually striking and different from the cozy aesthetic.

Wait, many games in the collection already use neon aesthetics. Let me go with something different - a warm, wooden tabletop aesthetic with realistic dominoes. This would be cozy and unique.

Actually, let me think about this more carefully. The visual style should be:

1. Distinct from other games in the collection
2. Appropriate for the game concept
3. Visually appealing

Looking at the collection, I see many neon/cyberpunk games. Let me go with a warm, cozy, wooden tabletop aesthetic. Dominoes are traditionally wooden, so this fits perfectly.

Color Palette:

• Background: Warm wood tones (#3D2817, #5C3A21, #8B5A2B)
• Dominoes: Ivory/cream (#F5E6D3) with dark dots (#2C1810)
• Targets: Golden glow (#FFD700)
• Walls: Dark wood (#2C1810)
• UI: Warm amber tones

Animation:

• Dominoes fall with a smooth rotation animation
• Each domino takes about 0.3 seconds to fall
• Chain reaction spreads with a slight delay between each domino
• Particle effects when targets are hit
• Screen shake when the chain starts

Levels: 10-12 levels with increasing complexity

1. Tutorial: Simple straight line
2. Turn: Make a 90-degree turn
3. Multiple targets: Hit 2 targets
4. Walls: Navigate around walls
5. Splitter: Use splitters to hit multiple paths
6. Gaps: Use boosters to jump gaps
7. Complex: Multiple paths, splitters, walls, gaps 8-12. Increasingly complex puzzles

Audio:

• Click sounds as dominoes fall (Web Audio API)
• Success chime when all targets are hit
• Ambient background

Let me now implement this. I'll create a single HTML file with everything self-contained.

Actually, wait. Let me reconsider the game concept one more time. The domino falling mechanic is essentially:

1. Place a domino at position (x, y) with direction d
2. When triggered, the domino at the start position falls in direction d
3. The falling domino knocks over the domino at the next position in direction d
4. That domino then falls in its own direction
5. Continue until no more dominoes to knock over

This is essentially a directed graph traversal. Each domino is a node with an outgoing edge in its direction. The chain follows edges until it reaches a dead end.

This is a nice puzzle mechanic! The player needs to:

1. Place dominoes to create a path from start to all targets
2. Orient each domino correctly so the chain flows in the right direction
3. Deal with obstacles (walls, gaps)
4. Use special dominoes (splitters, boosters) strategically

Let me implement this now. I'll make it really polished with:

• Beautiful wooden tabletop aesthetic
• Smooth domino falling animations
• Particle effects
• Web Audio sound
• Multiple levels
• Star ratings
• Persistent progress
• Full keyboard + mouse + touch support

Let me start coding!

Actually, I realize I should think about the implementation more carefully. The domino falling animation is key to the game's appeal. Let me think about how to implement it:

1. Each domino is a rectangle on the grid
2. When it "falls", it rotates 90 degrees from vertical to horizontal
3. The falling direction determines which way it rotates
4. After falling, it "lies down" in the direction of fall
5. The next domino in the path is then triggered

For the visual, I can use Canvas 2D to draw the dominoes. Each domino can be drawn as a 3D-looking rectangle with perspective. When falling, I can animate the rotation.

Actually, for a top-down view, dominoes would be seen from above. When they "fall", they would rotate from standing upright (small rectangle) to lying flat (longer rectangle in the direction of fall). This is simpler to implement.

Let me think about the visual representation:

• Standing domino: A small rectangle (e.g., 20x10 pixels) with dots
• Falling domino: Animate from standing to lying, with a rotation/scale effect
• Fallen domino: A longer rectangle (e.g., 40x10 pixels) in the direction of fall

Actually, for a more realistic look, I can use a pseudo-3D perspective:

• Standing domino: Drawn as a 3D box seen from a slight angle
• Falling domino: Animate the rotation from vertical to horizontal
• Fallen domino: Drawn as a flat rectangle

This would be more visually impressive but more complex to implement. Let me go with a simpler 2D approach first, with a slight isometric/perspective look.

OK, let me just start coding. I'll use Canvas 2D for rendering, with a warm wooden aesthetic.

Let me plan the code structure:

Let me think about the levels:

Level 1 (Tutorial):

• Grid: 8x5
• Start at (0, 2), Target at (7, 2)
• Place dominoes in a straight line from start to target
• 6 dominoes available, need 6

Level 2 (Turn):

• Grid: 8x5
• Start at (0, 2), Target at (4, 0)
• Need to make an L-shaped path
• Wall at (3, 2) blocking straight path

Level 3 (Multiple targets):

• Grid: 10x6
• Start at (0, 3), Targets at (9, 1) and (9, 5)
• Need splitter

Level 4 (Walls):

• Grid: 10x6
• Walls blocking direct path
• Need to navigate around

Level 5 (Splitter):

• Grid: 10x6
• Need to use splitter to hit two targets

Level 6 (Gaps):

• Grid: 12x8
• Gaps in the grid that need boosters

Level 7-10: Increasingly complex

Let me implement this now. I'll write the complete HTML file.

Actually, let me reconsider the visual approach. Instead of a top-down view, let me do a slight isometric/perspective view. This would make the dominoes look more 3D and the falling animation more dramatic.

Hmm, but isometric is more complex. Let me stick with top-down but make the dominoes look nice with shadows and highlights.

OK, let me start writing the code. I'll make it a single self-contained HTML file.

Let me think about the key features:

1. Grid-based domino placement
2. Direction selection (rotate dominoes)
3. Chain reaction simulation with animation
4. Multiple levels
5. Star ratings
6. Sound effects
7. Persistent progress
8. Beautiful visuals

Let me write the code now.

Actually, I want to make sure this game is really polished and impressive. Let me think about what would make it stand out:

1. Visual polish:

   • Warm wooden table background with wood grain texture
   • Realistic-looking dominoes with dots, shadows, and highlights
   • Smooth falling animation with rotation and shadow
   • Particle effects when targets are hit
   • Glow effects on targets
   • Screen shake when chain starts

2. Audio polish:

   • Click-clack sounds as dominoes fall (Web Audio API)
   • Different pitches for different domino types
   • Success chime
   • Ambient background

3. Gameplay polish:

   • Smooth interactions (click to place, click to rotate, click to remove)
   • Visual feedback for valid/invalid placements
   • Preview of the chain path
   • Undo functionality
   • Level select
   • Star ratings
   • Persistent progress

4. UI polish:

   • Clean, warm UI
   • Domino counter
   • Level info
   • Star display
   • Reset and Start buttons
   • Level select screen

Let me write the code now. I'll aim for a really polished, complete game.

Let me think about the rendering approach. I'll use Canvas 2D for the game board and HTML/CSS for the UI.

For the domino rendering:

• Standing domino: A small rectangle with a 3D effect (lighter top, darker bottom, shadow)
• Falling domino: Animate from standing to fallen, with rotation
• Fallen domino: A longer rectangle in the direction of fall

For the falling animation, I'll use a simple approach:

• Each domino has a fallProgress value from 0 to 1
• When falling, increment fallProgress over ~0.3 seconds
• Draw the domino at an intermediate state based on fallProgress
• The intermediate state is a rotation from vertical to horizontal

For the chain reaction:

• Use a queue of dominoes to fall
• Each domino starts falling when the previous one is ~50% fallen
• This creates a natural-looking chain reaction

Let me code this now.

Actually, I realize I should think about the grid size and cell size. Let me use:

• Grid: 12x8 cells
• Cell size: 50px
• Canvas: 600x400

This should fit nicely on most screens.

For mobile, I'll make the canvas responsive.

OK, let me write the code. I'll create the file at /space/games/domino-rally/index.html.

Let me think about the full implementation:

Let me now write the full implementation. I'll be thorough and make it really polished.

Let me think about the levels more carefully:

Level 1 (Tutorial - Straight Line):

Level 2 (Turn):

Level 3 (Wall):

Level 4 (Two Targets):

Level 5 (Gap):

Level 6+ (Complex):

• Combine walls, gaps, splitters, multiple targets

Let me implement this now. I'll write the complete game.

Actually, let me reconsider the game mechanics one more time. The key question is: how does the chain reaction work?

When a domino falls in direction D:

1. It falls from standing to lying in direction D
2. It "reaches" the next cell in direction D
3. If there's a domino in that cell, it gets knocked over (starts falling in its own direction)
4. If there's a target in that cell, it gets "hit" (knocked over)
5. If there's a wall or empty cell, the chain stops in that direction

For splitters:

• When a splitter falls in direction D, it sends the chain in two directions: D-left and D-right (perpendicular to D)
• Actually, a splitter should split the chain into two perpendicular directions. So if a splitter falls "right", it sends chains "up" and "down" as well.

Wait, that doesn't make sense physically. Let me think about this differently.

A splitter domino, when it falls, could:

1. Fall in its primary direction (like a normal domino)
2. Also trigger dominoes to its left and right (perpendicular)

So a splitter falling "right" would:

• Continue the chain to the right (normal)
• Also trigger dominoes above and below it

This makes sense as a "T-junction" or "crossroads" domino.

For boosters:

• A booster domino, when it falls, can "jump" over a gap
• It falls in its direction and reaches 2 cells ahead instead of 1
• This allows crossing gaps

OK, let me finalize the mechanics:

Standard Domino: Falls in direction D, knocks over the domino/target in the next cell in direction D.

Splitter Domino: Falls in direction D, knocks over dominoes/targets in ALL THREE adjacent cells (left, straight, right relative to D). So if falling right, it triggers up, right, and down.

Wait, that's too powerful. Let me make it trigger only the two perpendicular directions plus the forward direction. Actually, let me make it simpler:

Splitter Domino: Falls in direction D, knocks over dominoes/targets in the next cell in direction D AND the next cells in the two perpendicular directions. So if falling right, it triggers right, up, and down.

Actually, this is getting complicated. Let me simplify:

Standard Domino: Falls in direction D, knocks over the next cell in direction D.

Splitter Domino: Falls in direction D, knocks over the next cells in ALL FOUR directions (up, right, down, left). This creates a cross/plus pattern.

Wait, that's even more powerful. Let me think about this differently.

Actually, for a domino game, the splitter should make sense physically. A splitter could be a domino that, when it falls, also pushes dominoes to its sides. So:

Splitter Domino: When it falls in direction D (e.g., right), it:

1. Knocks over the next cell in direction D (right) - normal
2. Also knocks over the cells perpendicular to D (up and down) - split

This creates a T-shape chain. The splitter is the junction point.

Booster Domino: When it falls in direction D, it knocks over the cell 2 positions ahead in direction D (jumping over 1 cell). This allows crossing gaps.

OK, I think this is good. Let me implement it.

Actually, let me reconsider. For simplicity and clarity, let me have just standard dominoes and maybe one special type. Let me think about what makes the puzzle interesting:

The core puzzle is: create a path from start to all targets using dominoes, where each domino has a direction. The chain follows the directions. This is essentially a directed graph where you need to reach all target nodes.

Adding walls and gaps makes it more interesting. Splitters allow branching. Boosters allow jumping.

I think having all three types makes for a richer game. Let me implement all three.

OK, let me start coding now. I'll write the complete game.

Let me think about the rendering one more time. For the domino falling animation:

1. Standing state: Draw a small rectangle (e.g., 16x8 pixels) centered in the cell, with a 3D effect
2. Falling state: Animate the domino rotating from vertical to horizontal over ~0.3 seconds
   • At progress 0: Standing (16x8)
   • At progress 0.5: Mid-fall (partially rotated)
   • At progress 1: Fallen (lying flat, 32x8 in direction of fall)
3. Fallen state: Draw a flat rectangle in the direction of fall

For the 3D effect, I can use:

• A lighter color on top
• A darker color on the sides
• A shadow below

For the falling animation, I can use canvas transforms (translate, rotate, scale) to create the rotation effect.

Actually, for a top-down view, the "falling" animation would be:

• The domino starts as a small rectangle (standing upright, seen from above)
• As it falls, it extends in the direction of fall (like it's tipping over)
• When fully fallen, it's a long rectangle in the direction of fall

This is essentially a scale animation in the direction of fall. Let me implement it this way:

• Standing: width = 16, height = 8 (small rectangle)
• Falling: width = 16 + 16*progress, height = 8 (extending in direction of fall)
• Fallen: width = 32, height = 8 (long rectangle in direction of fall)

Wait, this doesn't look like a domino falling. Let me think about this differently.

In a top-down view, a standing domino looks like a small rectangle (its footprint). When it falls, it tips over and lies flat, extending in the direction of fall. The animation would be:

1. Start: Small rectangle (footprint of standing domino)
2. Mid-fall: The domino is at an angle, so its projection on the ground is between small and large
3. End: Long rectangle (full length of fallen domino)

I can simulate this by animating the length of the rectangle from short to long, with a slight rotation for effect.

Actually, for a more dramatic effect, I can use a pseudo-3D approach:

• Draw the domino as a 3D box
• Animate the rotation from vertical to horizontal
• This gives a realistic falling effect

But this is more complex. Let me go with the simpler 2D approach first, with some visual tricks to make it look good.

Here's my approach:

1. Each domino has a position (gridX, gridY) and direction (up/right/down/left)
2. Standing domino: Draw as a small rounded rectangle with dots, with a shadow
3. Falling domino: Animate using canvas transforms - rotate and scale to simulate tipping over
4. Fallen domino: Draw as a long rounded rectangle in the direction of fall

For the falling animation, I'll use:

• ctx.save()
• ctx.translate(centerX, centerY)
• ctx.rotate(directionAngle * fallProgress * Math.PI/2) - rotate 90 degrees
• ctx.scale(1, 1 - fallProgress * 0.5) - flatten slightly
• Draw the domino
• ctx.restore()

Actually, this is getting complicated. Let me simplify:

For a top-down view, I'll represent the domino as:

• Standing: A small rectangle (e.g., 14x14 with rounded corners) with a 3D shadow effect
• Falling: Animate the rectangle extending in the direction of fall
• Fallen: A long rectangle (e.g., 28x14) in the direction of fall

The animation will interpolate the rectangle's dimensions from standing to fallen.

Let me just code it and see how it looks. I can always adjust.

OK, I'm going to start writing the code now. Let me create the complete game file.

Let me think about the overall structure:

1. HTML structure
2. CSS styles (warm wooden aesthetic)
3. JavaScript: a. Game state b. Level definitions c. Rendering (Canvas 2D) d. Input handling (mouse, touch, keyboard) e. Chain reaction simulation f. Animation loop g. Audio (Web Audio API) h. UI updates i. Local storage for progress

Let me write it all now.

Actually, I want to make sure the game is really good. Let me think about what would make it stand out:

1. Beautiful visuals: Warm wooden table with wood grain, realistic dominoes with dots, soft shadows, warm lighting
2. Satisfying animation: Smooth domino falling with realistic timing, chain reaction with natural delays
3. Good audio: Click-clack sounds with varying pitch, success chime
4. Engaging puzzles: 10+ levels with increasing complexity, star ratings
5. Polished UI: Clean, warm interface with level select, domino counter, star display
6. Accessibility: Full keyboard, mouse, and touch support

Let me code this now. I'll write the complete file.

One more thing - let me think about the grid size. I want it to be large enough for interesting puzzles but small enough to fit on screen. Let me use:

• Grid: 12x8 (96 cells)
• Cell size: 48px
• Canvas: 576x384

This should work well on most screens. For mobile, I'll scale it down.

OK, let me write the code now!

Actually, I realize I should think about one more thing: the domino direction and how it's displayed. In a top-down view:

• Standing domino: A small square/rectangle with an arrow indicating direction
• Direction indicator: An arrow or the domino's dots arranged to show direction

For the direction, I can:

1. Draw an arrow on the domino
2. Draw the domino as a small rectangle oriented in the direction of fall
3. Use color coding

I think option 2 is best - draw the standing domino as a small rectangle oriented in the direction it will fall. So a domino that will fall "right" is a small horizontal rectangle, and one that will fall "up" is a small vertical rectangle.

Wait, actually, a standing domino seen from above would look the same regardless of direction (it's a small rectangle/square footprint). The direction is which way it will tip over. So I need a direction indicator.

Let me use:

• Standing domino: A small rectangle with an arrow pointing in the fall direction
• The rectangle is oriented perpendicular to the fall direction (like a real domino standing on its narrow end)

So a domino that falls "right" would be:

• A small vertical rectangle (narrow end facing right)
• With an arrow or indicator pointing right

When it falls:

• It tips over to the right
• Becomes a horizontal rectangle extending to the right

This makes sense! Let me implement it this way.

For the domino visual:

• Standing: Small rectangle (8x16 pixels for horizontal fall, 16x8 for vertical fall) with 3D effect and direction arrow
• Fallen: Long rectangle (32x16 for horizontal, 16x32 for vertical) in the direction of fall

Wait, I need to think about this more carefully. A domino is a rectangular block. When standing, it's tall and narrow. When it falls, it lies flat and long.

In a top-down view:

• Standing domino (will fall right): A small rectangle, maybe 10x20 pixels (narrow in the fall direction, wide perpendicular)
  • Actually, a standing domino seen from above would look like its footprint, which is a small rectangle. The orientation of the footprint doesn't change based on fall direction.
  • But for gameplay clarity, I should orient the footprint perpendicular to the fall direction.

Let me just go with:

• Standing domino: A small rectangle (e.g., 12x20 pixels) oriented perpendicular to the fall direction, with a 3D effect (lighter top, darker sides) and a small arrow or dot pattern indicating direction
• Fallen domino: A long rectangle (e.g., 36x20 pixels) in the direction of fall, lying flat

For the falling animation:

• Interpolate from standing (12x20, perpendicular) to fallen (36x20, in direction)
• This means the rectangle rotates 90 degrees and extends in the fall direction

I can implement this with canvas transforms:

1. Translate to the domino's position
2. Rotate by fallProgress * 90 degrees in the fall direction
3. Scale to interpolate from standing to fallen size
4. Draw the rectangle

Let me code this now. I'll figure out the exact transforms as I go.

OK, I'm going to write the complete game now. Let me create the file.

Let me think about the level designs more carefully:

Level 1 - "First Steps" (Tutorial):

Solution: Place 6 standard dominoes pointing right from S to T.

Level 2 - "Turn Around":

Solution: Go right 6, then up 2.

Level 3 - "Wall Bounce":

Solution: Go right 2, up 1, right 4 (over wall? no, around), up 2. Wait, walls block. Need to go around.

Actually, let me redesign:

Solution: Go right 2, up 2, right 4, up 1. Wait, the wall is at row 2, cols 2-4. So:

• Start at (0, 3)
• Go right to (1, 3)
• Go up to (1, 1) - 2 steps up
• Go right to (6, 1) - 5 steps right
• Go up to (6, 0) - 1 step up
• Target at (7, 0) - 1 step right Total: 1 + 2 + 5 + 1 + 1 = 10 dominoes

Hmm, that's exactly 10. Let me adjust to make it a bit easier with some margin.

Actually, let me not overthink the levels. I'll create them as I code and adjust. Let me start writing the game now.

Let me think about the code structure one more time:

OK, let me write the complete game now. I'll make it really polished.

Let me think about the chain reaction simulation:

Actually, let me reconsider the start mechanic. Options:

1. The start cell has a pre-placed domino with a fixed direction
2. The player places a domino on the start cell and chooses its direction
3. The start cell "pushes" in a direction, and the player places a domino next to it

I think option 1 is simplest and clearest. The start cell has a domino that falls in a specific direction (defined by the level). The player places dominoes on other cells to continue the chain.

Wait, but then the player needs to know which direction the start domino falls. I can show this with an arrow on the start cell.

Actually, let me make it even simpler: the start cell is a "pusher" that pushes the domino to its right (or in a level-defined direction). The player places dominoes on all cells including next to the start.

Hmm, this is getting complicated. Let me simplify:

• The start cell has a pre-placed domino with a fixed direction (shown by an arrow)
• The player cannot remove or change this domino
• When "Start" is pressed, this domino falls first
• The chain continues from there

This is clear and simple. Let me implement it this way.

For the chain reaction:

Wait, I need to reconsider the splitter. A splitter should split the chain, not trigger in all 4 directions. Let me think about this:

A splitter domino, when it falls in direction D:

• Continues the chain in direction D (normal)
• Also starts new chains in the two perpendicular directions

So if a splitter falls "right":

• Continue right (normal)
• Also go up and down (split)

This means the splitter triggers cells in 3 directions: forward, left-perpendicular, right-perpendicular.

For a splitter falling right: trigger right, up, down For a splitter falling up: trigger up, left, right For a splitter falling left: trigger left, up, down For a splitter falling down: trigger down, left, right

This is better! The splitter creates a T-junction.

For the booster:

• When it falls in direction D, it reaches 2 cells ahead instead of 1
• This allows jumping over a gap

Wait, but for the booster, I also need to check that the jumped-over cell is a gap (or empty). If it's a wall, the booster can't jump over it.

OK, this is getting complex but manageable. Let me write the complete game now.

Actually, I realize I should also think about what happens when a domino is "knocked over" by a chain coming from a direction different from its own fall direction.

For example, if a chain is going right and hits a domino that's oriented to fall up, what happens?

Options:

1. The domino falls in its own direction (up), regardless of which direction it was hit from
2. The domino falls in the direction it was hit from (right)

Option 1 is more realistic (a domino falls in the direction it's oriented) but can lead to confusing chains. Option 2 is less realistic but makes the puzzle more intuitive (the chain follows the path you create).

Actually, in real dominoes, a domino falls in the direction it's pushed. So if a chain going right hits a domino, that domino falls right (continuing the chain). The domino's orientation doesn't matter - it falls in the direction of the push.

But in my game, the player orients each domino. So the direction should matter. Let me go with option 1: each domino falls in its own direction when knocked over. This makes the puzzle about planning the directions correctly.

Wait, but this could lead to situations where a domino is hit from the left but falls upward, which doesn't make physical sense.

Let me think about this differently. In my game:

• The player places dominoes and orients them
• When the chain reaches a domino, it falls in its oriented direction
• This is the puzzle: orient each domino so the chain flows correctly

This is like a directed graph where each node has one outgoing edge. The chain follows the edges. The puzzle is to set up the edges correctly.

I think this is the right approach. It's a puzzle game, not a physics simulation. The dominoes fall in their oriented direction, and the player needs to plan the chain.

OK, let me finalize the mechanics:

1. Player places dominoes on empty cells
2. Each domino has a direction (up/right/down/left) and a type (standard/splitter/booster)
3. The start cell has a pre-placed domino with a fixed direction
4. When "Start" is pressed, the start domino falls in its direction
5. When a domino is 50% fallen, it triggers the next cell(s) in its direction(s)
6. If the next cell has a domino, that domino starts falling in its own direction
7. If the next cell is a target, the target is hit
8. If the next cell is a wall, gap (without booster), or empty, the chain stops in that direction
9. Win condition: all targets are hit
10. Lose condition: the chain stops before hitting all targets

This is clear and makes for a good puzzle. Let me implement it now.

One more thing: I need to handle the case where a domino is triggered multiple times (e.g., by a splitter sending chains that converge). I'll use a flag to ensure each domino only falls once.

OK, let me write the complete game now. I'll create the file.

Let me also think about the visual design one more time:

Color Palette (warm wooden tabletop):

• Background: Dark wood (#2a1810 to #3d2817)
• Table surface: Warm wood (#5c3a21 to #8b5a2b) with grain texture
• Grid lines: Subtle dark lines (#3d2817 with low opacity)
• Standing domino: Ivory (#f5e6d3) with dark dots (#2c1810)
• Fallen domino: Slightly darker ivory (#e8d5c0)
• Start domino: Golden/amber (#ffa500)
• Target: Glowing gold (#ffd700) with pulsing animation
• Wall: Dark wood (#1a0f08)
• Gap: Dark hole (#0a0500)
• Splitter domino: Purple-tinted (#d4a5e8)
• Booster domino: Blue-tinted (#a5d4e8)
• UI: Warm amber tones (#ffa500, #ff8c00)

Typography: System font, warm and clean

Effects:

• Soft shadows under dominoes
• Glow on targets
• Particle effects when targets are hit
• Screen shake when chain starts
• Wood grain texture on background

OK, I'm going to write the code now. Let me create the complete game file.

I'll structure the code as follows:

1. HTML structure
2. CSS (warm wooden aesthetic, responsive)
3. JavaScript: a. Constants and configuration b. Level definitions c. Game state d. Canvas rendering e. Input handling f. Chain reaction simulation g. Animation loop h. Audio system i. UI management j. Local storage k. Initialization

Let me write it all now. This will be a large file but I'll make it complete and polished.

Actually, let me think about the level designs one more time. I want 10 levels with good progression:

Level 1 - "First Steps":

• 8x4 grid
• Start at (0,1) pointing right, Target at (7,1)
• 6 standard dominoes
• Straight line, tutorial

Level 2 - "Corner":

• 8x5 grid
• Start at (0,3) pointing right, Target at (7,0)
• 10 standard dominoes
• L-shaped path

Level 3 - "Detour":

• 10x5 grid
• Start at (0,2) pointing right, Target at (9,2)
• Wall at (3,2), (4,2), (5,2)
• 12 standard dominoes
• Go around the wall

Level 4 - "Twin Targets":

• 10x6 grid
• Start at (0,2) pointing right, Targets at (9,0) and (9,5)
• 12 standard + 1 splitter
• Use splitter to branch

Level 5 - "Mind the Gap":

• 10x6 grid
• Start at (0,2) pointing right, Target at (9,2)
• Gaps at (4,2), (5,2)
• 10 standard + 2 booster
• Use boosters to jump gaps

Level 6 - "Maze":

• 12x7 grid
• Start at (0,3) pointing right, Target at (11,3)
• Multiple walls creating a maze
• 15 standard dominoes

Level 7 - "Triple Threat":

• 12x8 grid
• Start at (0,3) pointing right, Targets at (11,0), (11,4), (11,7)
• 15 standard + 2 splitter
• Multiple branches

Level 8 - "Obstacle Course":

• 12x8 grid
• Start at (0,3) pointing right, Targets at (11,0), (11,7)
• Walls and gaps
• 15 standard + 1 splitter + 2 booster

Level 9 - "Complex":

• 12x8 grid
• Multiple targets, walls, gaps
• All domino types

Level 10 - "Master":

• 12x8 grid
• Most complex puzzle
• All domino types, tight domino budget

Let me implement these levels. I'll define them as data structures.

OK, I'm going to write the code now. Let me create the file.

Actually, I realize I should think about the grid representation for levels. I'll use a string-based representation for clarity:

For the start direction, I'll use a separate field.

Let me define levels like this:

This is clean and easy to work with. Let me implement it.

OK, I'm writing the code now. Let me create the complete file.

Let me think about the canvas size. I want it to be responsive. I'll use a fixed internal resolution and scale it with CSS.

Internal resolution:

• Grid: 12x8 cells, 48px each = 576x384
• Plus some padding for the table edge: 624x432

I'll make the canvas scale to fit the container while maintaining aspect ratio.

For smaller grids (8x4, 8x5, 10x5, 10x6), I'll center the grid in the canvas.

Actually, let me use a fixed canvas size that fits the largest grid (12x8) and center smaller grids within it.

Canvas: 624x432 (1248 + 224 padding, 848 + 224 padding)

For each level, I'll calculate the offset to center the grid.

OK, let me write the code now. I'm going to create the complete game file.

Let me also think about the UI layout:

For mobile, I'll stack everything vertically and make the canvas responsive.

OK, let me write the complete game now. I'll make it really polished and complete.

Let me think about one more thing: the domino placement interaction.

Mouse/Touch:

• Click on empty cell: Place selected domino type with default direction (right)
• Click on placed domino: Rotate direction (right -> down -> left -> up -> right)
• Right-click on placed domino: Remove domino
• Or: Click on placed domino to cycle through directions, then remove

Actually, let me make it simpler:

• Click on empty cell: Place domino (default direction: right)
• Click on placed domino: Rotate direction
• Shift+click or right-click on placed domino: Remove
• Or: Have a "remove" mode toggle

For touch:

• Tap on empty cell: Place domino
• Tap on placed domino: Rotate direction
• Long press on placed domino: Remove

Let me also add a "remove" button/mode for clarity.

Actually, let me use this interaction:

• Click on empty cell: Place domino with current direction (default: right)
• Click on placed domino: Rotate direction (right -> down -> left -> up)
• Right-click / long-press on placed domino: Remove
• Keyboard: R to rotate selected, Delete to remove

For the direction, I'll show the current default direction with an indicator, and clicking cycles through directions.

Wait, actually, let me make it even simpler:

• Click on empty cell: Place domino (direction: right by default)
• Click on placed domino: Cycle direction (right -> down -> left -> up -> right)
• Right-click on placed domino: Remove
• For touch: tap to place/cycle, long-press to remove

This is intuitive. Let me implement it.

OK, I'm going to write the complete game now. Let me create the file.

Let me also think about the keyboard controls:

• 1, 2, 3: Select domino type (standard, splitter, booster)
• R: Rotate direction of last placed domino (or cycle default direction)
• Space: Start chain
• Backspace/Delete: Reset
• Arrow keys: Move cursor (for keyboard-only play)

Actually, for simplicity, let me focus on mouse/touch interaction and add a few keyboard shortcuts:

• 1, 2, 3: Select domino type
• Space: Start chain
• R: Reset
• Escape: Back to level select

OK, let me write the code now. I'll create the complete game file.

I'm going to write a really polished, complete game. Let me start.

Actually, I want to think about one more visual detail: the domino appearance.

A real domino has two halves, each with dots (pips) representing numbers. For my game, I can:

1. Draw dominoes with realistic pips
2. Use simpler colored dominoes
3. Use a stylized representation

For the warm wooden aesthetic, I'll go with option 1: realistic-looking dominoes with pips. Each domino will have:

• An ivory/cream colored body
• A dividing line in the middle
• Pips on each half (random or fixed numbers)
• A 3D effect with highlights and shadows

For different domino types:

• Standard: Normal ivory with dark pips
• Splitter: Purple-tinted with a "split" symbol
• Booster: Blue-tinted with a "jump" symbol

For the direction indicator:

• An arrow on the domino pointing in the fall direction
• Or the pips arranged to indicate direction

I think an arrow is clearest. Let me draw a small arrow on each domino indicating its fall direction.

OK, let me write the code now. I'm going to create the complete game file.

Let me think about the wood grain texture. I can create a procedural wood grain using canvas:

1. Fill with a base wood color
2. Draw horizontal lines with varying opacity and color
3. Add some noise

Or I can use a CSS gradient for the background and draw the grid on canvas.

Let me use a combination:

• CSS gradient for the page background (dark wood)
• Canvas-drawn wood grain for the table surface
• Canvas-drawn grid lines

For the wood grain, I'll draw horizontal lines with varying colors and opacity to simulate wood grain.

OK, I'm going to write the code now. Let me create the complete game file. I'll make it really polished and complete.

Let me plan the code structure one more time:

OK, this is a good structure. Let me write the complete code now.

I need to be careful about the canvas rendering. Let me think about the rendering pipeline:

1. Clear canvas
2. Draw table surface (wood grain)
3. Draw grid lines
4. Draw cells (walls, targets, gaps, start)
5. Draw dominoes (standing, falling, fallen)
6. Draw particles
7. Draw UI overlays (if any)

For the animation loop:

1. Update game state (fall progress, particles, etc.)
2. Check win/lose conditions
3. Render

Let me write the code now. I'll create the complete file.

One more consideration: the canvas resolution. For crisp rendering on high-DPI displays, I should set the canvas internal resolution to match the display resolution * devicePixelRatio. But for simplicity, I'll use a fixed internal resolution and let CSS scale it.

Internal resolution: 624x432 (1248 + 224, 848 + 224) CSS: max-width: 100%, height: auto

This should work well.

OK, I'm writing the code now. Let me create the complete game file. This will be a large file but I'll make it complete and polished.

Let me think about the wood grain rendering. I'll create a function that draws wood grain on the canvas:

But this would be different every frame. I should pre-render the wood grain to an offscreen canvas and reuse it.

Then in the render function:

This is more efficient. Let me implement it this way.

OK, I'm going to write the complete game now. Let me create the file. I'll write it all at once.

Let me think about the complete feature list:

1. ✅ Title screen with level select
2. ✅ Game screen with canvas
3. ✅ Domino placement (click to place, click to rotate, right-click to remove)
4. ✅ Three domino types (standard, splitter, booster)
5. ✅ Chain reaction simulation with animation
6. ✅ Win/lose detection
7. ✅ Star ratings
8. ✅ Sound effects (Web Audio API)
9. ✅ Persistent progress (localStorage)
10. ✅ 10 levels with increasing complexity
11. ✅ Warm wooden aesthetic
12. ✅ Responsive design
13. ✅ Keyboard shortcuts
14. ✅ Touch support
15. ✅ Particle effects
16. ✅ Screen shake

Let me write the code now. I'll create the complete file.

OK here's my plan for the code. I'll write it all in one go. Let me be thorough and make it really good.

Actually, I realize I should also think about the "lose" condition. When does the player lose?

The player loses when:

1. The chain reaction completes (all dominoes have fallen) but not all targets are hit
2. The player runs out of dominoes and can't reach all targets

For condition 2, the player can just reset and try again. For condition 1, I need to detect when the chain is complete (no more falling dominoes) and check if all targets are hit.

But I should also add a small delay after the chain completes before showing the win/lose screen, to let the player see the final state.

OK, let me write the code now. I'll create the complete game file.

Let me also think about the "Start" button behavior:

• When clicked, if there are dominoes placed, start the chain
• Disable the button during simulation
• Show "Reset" to clear and try again

And the "Reset" button:

• Clear all placed dominoes
• Reset targets
• Return to editing phase

OK, I'm writing the code now. Let me create the complete file. I'll make it really polished and complete.

Let me think about the file size. This will be a large file (probably 1000+ lines). I'll write it all at once.

Let me start writing now.

Actually, one more thing. I want to make sure the game is really visually appealing. Let me think about the visual details:

1. Table surface: Warm wood with grain texture, slightly darker edges (vignette effect)
2. Grid: Subtle dark lines, barely visible
3. Cells:
   • Empty: Slightly lighter than table
   • Wall: Dark wood blocks with 3D effect
   • Target: Golden glowing circle with pulsing animation
   • Start: Amber colored tile with arrow
   • Gap: Dark hole with shadow
4. Dominoes:
   • Standing: Small ivory rectangle with 3D effect, pips, direction arrow, shadow
   • Falling: Animated rotation/extension
   • Fallen: Long ivory rectangle lying flat, with shadow
5. Effects:
   • Particle burst when target is hit
   • Screen shake when chain starts
   • Glow effects on targets
   • Soft shadows under dominoes

For the domino 3D effect, I can use:

• A lighter color on top edge
• A darker color on bottom edge
• A shadow below

For the falling animation, I'll use canvas transforms:

• Translate to domino center
• Rotate by fall direction angle * fall progress
• Scale to simulate the domino tipping over
• Draw the domino

Let me think about the exact transform:

For a domino at position (px, py) with direction RIGHT:

• Standing: Draw a small rectangle centered at (px, py), size (w=12, h=20)
• The domino tips to the right
• Fallen: Draw a long rectangle starting at (px, py), extending right, size (w=36, h=20)

For the animation:

• At progress 0: Standing (small rect at center)
• At progress 0.5: Mid-fall (rect is rotating, extending right)
• At progress 1: Fallen (long rect extending right)

I can simulate this by:

1. Translating to the pivot point (the right edge of the domino)
2. Rotating by -90° * progress (tipping to the right)
3. Drawing the rectangle

Wait, the pivot point should be the bottom-right corner of the standing domino (the edge that stays on the ground while the domino tips over).

Actually, in a top-down view, the pivot is the edge of the domino footprint that's in the direction of fall. For a domino falling right, the pivot is the right edge of its footprint.

Let me think about this more carefully:

Standing domino (falling right):

• Footprint: small rect at (px, py), size (12, 20) - narrow in x, wide in y
• The domino tips to the right, pivoting on its right edge
• As it tips, it extends to the right

Fallen domino (fallen right):

• Lying flat: long rect starting at (px, py), extending right, size (36, 20)

For the animation, I can:

1. Translate to the pivot point (right edge of footprint: px + 6, py)
2. Rotate by -90° * progress (clockwise = tipping right)
3. Draw the standing rectangle offset so its right edge is at the pivot

Actually, this is getting complicated. Let me use a simpler approach:

For the falling animation, I'll interpolate the domino's shape from standing to fallen:

• Standing: small rect (12x20) at center
• Fallen: long rect (36x20) extending in fall direction from center

I'll interpolate the width and position:

• width = 12 + (36-12) * progress = 12 + 24*progress
• The rect extends from the center in the fall direction

For a domino falling right:

• x = px - 6 + (0 - (-6)) * progress = px - 6 + 6*progress (left edge moves right)
• Wait, this doesn't work right.

Let me think about it differently. The domino starts as a small rect centered at (px, py) and becomes a long rect extending in the fall direction.

For falling right:

• Standing: rect from (px-6, py-10) to (px+6, py+10) - 12x20 centered
• Fallen: rect from (px-6, py-10) to (px+30, py+10) - 36x20 extending right

So the left edge st

Good, I have the skill guidelines. Now let me design and build the game.

I've decided to build "Domino Rally" - a domino chain reaction puzzle game. This is:

1. NOT in the existing collection (Reaction Chain is about blast radius nodes, not dominoes)
2. Visually satisfying (watching dominoes fall in sequence)
3. Mechanically engaging (planning chain reactions with directional dominoes)
4. Educational (cause and effect, spatial planning, chain reactions)
5. Achievable with good quality
6. Has depth (multiple levels, increasing complexity, star ratings)

Let me now write the complete game. I'll create it at /space/games/domino-rally/index.html.

The game will feature:

• A warm wooden tabletop aesthetic (distinct from the many neon games in the collection)
• Grid-based domino placement with directional orientation
• Three domino types: Standard, Splitter (branches chain), Booster (jumps gaps)
• Chain reaction simulation with smooth falling animation
• 10 levels with increasing complexity
• Star ratings based on domino efficiency
• Web Audio API sound effects (click-clack of falling dominoes)
• Particle effects when targets are hit
• Persistent progress via localStorage
• Full keyboard, mouse, and touch support

Let me write the complete code now.

The JavaScript syntax is valid. Now let me do a more thorough logic test by simulating the chain reaction logic to make sure it works correctly.

I see the issues now:

Level 5: The domino at (9,1) points UP, which triggers (9,0). But (9,0) is EMPTY, not the target. The target is at (10,0). So I need the domino at (9,0) to point RIGHT, or I need to place a domino at (9,0) pointing RIGHT to reach (10,0).

Wait, but (9,0) is empty and not a target. The target is at (10,0). So I need:

• (9,1) points UP -> triggers (9,0) which is empty -> chain stops
• I need (9,1) to point UP, and then have a domino at (9,0) pointing RIGHT -> triggers (10,0) target

But wait, can I place a domino at (9,0)? (9,0) is an empty cell, so yes! Let me add (9,0,RIGHT) to the solution.

Actually wait, the target is at (10,0). Let me re-check: grid[0] = '..........T', so T is at position 10, row 0. So target is at (10,0).

So the path should be: ... -> (9,1) UP -> (9,0) RIGHT -> target(10,0)

I need to add (9,0,RIGHT) to the solution. That makes 11 dominoes, par is 10. Hmm, over par.

Actually, let me reconsider. Maybe I should use a different path. What if I go right along row 1 and then up at the end?

(0,2)R -> (1,2)R -> (2,2)R -> (3,2)UP -> (3,1)R -> (4,1)R -> (5,1)R -> (6,1)R -> (7,1)R -> (8,1)R -> (9,1)UP -> (9,0)R -> target(10,0)

That's 11 dominoes. Par is 10. Over by 1.

Alternatively, use boosters to jump the gaps: (0,2)R -> (1,2)R -> (2,2)R -> (3,2) Booster -> (5,2) - but (5,2) is a gap! Can't place domino there.

Hmm, booster at (3,2) jumps to (5,2) which is a gap. No domino can be placed there.

What about booster at (3,2) pointing right, dist=2, reaches (5,2) which is a gap. The gap cell has no domino and is not a target, so chain stops.

What if I use TWO boosters? Booster at (3,2) jumps to (5,2) - gap, no good.

Actually, the booster jumps OVER 1 cell. From (3,2), it skips (4,2) and lands on (5,2). But (5,2) is a gap.

What if I use a booster at (2,2)? It skips (3,2) and lands on (4,2) which is a gap. No good.

The gaps are at (4,2) and (5,2), two consecutive. A booster can only skip 1 cell. So it can't jump both gaps.

I think the only solution is to go around. Let me try a more efficient path:

(0,2)R -> (1,2)R -> (2,2)R -> (3,2)UP -> (3,1)R -> (4,1)R -> (5,1)R -> (6,1)R -> (7,1)R -> (8,1)R -> (9,1)UP -> (9,0)R -> target(10,0)

That's 11 dominoes. Par is 10. I should increase the par to 11, or find a better path.

Actually, wait. What if I go up earlier and take a shorter path?

(0,2)R -> (1,2)UP -> (1,1)R -> (2,1)R -> (3,1)R -> (4,1)R -> (5,1)R -> (6,1)R -> (7,1)R -> (8,1)R -> (9,1)UP -> (9,0)R -> target(10,0)

That's still 11 dominoes. The minimum path from (0,2) to (10,0) going around the gaps is:

• Go right some, up 1, right to x=9, up 1, right 1 to target
• The gaps are at (4,2) and (5,2), so I need to be on row 1 when passing x=4 and x=5
• Shortest path: right 1, up 1, right 8, up 1, right 1 = 11 dominoes

So the minimum is 11. I should set par to 11 for this level. Or I could redesign the level to have only 1 gap, making it possible with 10 dominoes.

Let me redesign Level 5 to have only 1 gap: grid: ['..........T','...........','S....G.....','...........','...........'] Gap at (5,2) only. Then: (0,2)R -> (1,2)R -> (2,2)R -> (3,2)R -> (4,2) Booster -> (6,2)R -> (7,2)R -> (8,2)R -> (9,2)UP -> (9,1)UP -> (9,0)R -> target(10,0)

Wait, that's 10 dominoes (excluding start). Let me count: (1,2)R, (2,2)R, (3,2)R, (4,2)Booster, (6,2)R, (7,2)R, (8,2)R, (9,2)UP, (9,1)UP, (9,0)R = 10 dominoes. Par = 10!

But wait, (9,0) is empty, not a target. Target is at (10,0). So (9,0)R -> target(10,0). That works!

Actually, let me re-check: (9,0) is in row 0 = '..........T'. Position 9 is '.', position 10 is 'T'. So (9,0) is empty and (10,0) is target. Good.

So with 1 gap at (5,2), the solution is: (1,2)R, (2,2)R, (3,2)R, (4,2)Booster, (6,2)R, (7,2)R, (8,2)R, (9,2)UP, (9,1)UP, (9,0)R = 10 dominoes, par = 10.

Let me update the level.

Level 7: The issue is that the splitter at (8,2) triggers (9,2) which is EMPTY, not a target. The target is at (10,2). So I need a domino at (9,2) pointing RIGHT to reach (10,2).

But wait, (9,2) is empty. Can I place a domino there? Yes! Let me add (9,2,RIGHT) to the solution.

With (9,2,RIGHT): the splitter at (8,2) triggers (9,2) which has a domino pointing RIGHT, which then triggers (10,2) target.

So the solution for L7 becomes: Standard: [1,4,RIGHT],[2,4,UP],[2,3,UP],[2,2,RIGHT],[3,2,RIGHT],[4,2,RIGHT],[5,2,RIGHT],[6,2,RIGHT],[7,2,RIGHT],[8,1,UP],[8,0,RIGHT],[9,0,RIGHT],[8,3,DOWN],[8,4,RIGHT],[9,2,RIGHT],[9,5,DOWN],[9,6,RIGHT] Splitter: [8,2,RIGHT],[9,4,RIGHT]

That's 17 standard + 2 splitter = 19 total. Budget is 18+2=20. Par is 16. Over par.

Hmm, let me try to optimize. Can I use the splitter more efficiently?

Actually, let me reconsider. The splitter at (8,2) triggers right (9,2), up (8,1), down (8,3).

• (9,2) needs a domino pointing right to reach (10,2). That's 1 extra domino.
• (8,1) up -> (8,0) right -> (9,0) right -> target (10,0). That's 3 dominoes.
• (8,3) down -> (8,4) right -> (9,4) splitter -> (9,5) down -> (9,6) right -> target (10,6). That's 4 standard + 1 splitter.

Path to splitter at (8,2): (1,4)R, (2,4)U, (2,3)U, (2,2)R, (3,2)R, (4,2)R, (5,2)R, (6,2)R, (7,2)R = 9 standard

Total: 9 + 1 + 3 + 4 = 17 standard + 2 splitter = 19. Par 16.

Can I do better? What if I place the splitter at (9,2) instead? Splitter at (9,2) pointing right: triggers (10,2) target!, (9,1) up, (9,3) down.

• (10,2) is the target - hit directly!
• (9,1) up -> (9,0) right -> target (10,0). 2 dominoes.
• (9,3) down -> (9,4) -> need to reach (10,6). (9,4) right? No, (10,4) is not a target. (9,3) down -> (9,4) down -> (9,5) down -> (9,6) right -> target (10,6). 3 dominoes.

Path to splitter at (9,2): (1,4)R, (2,4)U, (2,3)U, (2,2)R, (3,2)R, (4,2)R, (5,2)R, (6,2)R, (7,2)R, (8,2)R = 10 standard

Total: 10 + 2 + 3 = 15 standard + 1 splitter = 16 = par!

But I need a second splitter for the budget. Actually, the budget says 2 splitters, but I only need 1. That's fine - extra budget is OK.

Wait, but I also need to reach (10,0) from (9,1). (9,1) up -> (9,0) right -> target (10,0). But (9,0) is empty, so I need a domino at (9,0) pointing right. That's 1 domino.

And (9,1) needs a domino pointing up. That's another domino.

So: (9,1)U, (9,0)R = 2 dominoes for target (10,0). And: (9,3)D, (9,4)D, (9,5)D, (9,6)R = 4 dominoes for target (10,6).

Total: 10 (path) + 1 (splitter) + 2 (target 10,0) + 4 (target 10,6) = 16 standard + 1 splitter = 17 total. Par 16. Over by 1.

Hmm. Let me try another approach. What if I use 2 splitters?

Splitter1 at (9,2) pointing right: triggers (10,2) target, (9,1) up, (9,3) down. Splitter2 at (9,4) pointing right: triggers (10,4) - no target, (9,3) - already triggered, (9,5) down. (9,5) down -> (9,6) right -> target (10,6). 2 dominoes.

But how do I get from splitter1 to splitter2? (9,3) down -> (9,4) splitter2. So (9,3) needs a domino pointing down. But (9,3) is triggered by splitter1's down direction. So (9,3) would need to be a domino pointing down.

Wait, splitter1 at (9,2) triggers (9,3) in the down direction. If there's a domino at (9,3) pointing down, it falls and triggers (9,4). If (9,4) is a splitter, it triggers (10,4), (9,3) already fallen, (9,5) down.

(9,5) down -> (9,6) right -> target (10,6). 2 dominoes.

And for (10,0): (9,1) up -> (9,0) right -> target (10,0). 2 dominoes.

Path to splitter1: 10 standard. (9,3)D: 1 standard. Splitter2 at (9,4): 1 splitter. (9,5)D, (9,6)R: 2 standard. (9,1)U, (9,0)R: 2 standard. Splitter1 at (9,2): 1 splitter.

Total: 10 + 1 + 2 + 2 = 15 standard + 2 splitter = 17. Par 16. Still over by 1.

Hmm. Let me try to shorten the path to the splitter.

What if I go up earlier? (0,4)R -> (1,4)U -> (1,3)U -> (1,2)U -> (1,1)U -> (1,0)R -> (2,0)R -> ... -> (9,0)R -> target(10,0)

Wait, that hits target (10,0) first. Then I need to also hit (10,2) and (10,6).

Actually, let me think about this differently. The minimum path from (0,4) to (9,2) is:

• Right 9, up 2 = 11 dominoes (going right along row 4 to (9,4), then up to (9,2))
• Or up 2, right 9 = 11 dominoes (going up to (0,2), then right to (9,2))
• Or some combination

The minimum is 11 dominoes (Manhattan distance = 9+2 = 11). But I need to place 11 dominoes (excluding start).

Wait, the start is at (0,4). The path from (0,4) to (9,2) requires at least 11 steps (9 right + 2 up). But the start domino is pre-placed, so I need 11 placed dominoes to reach (9,2).

Then from (9,2) splitter, I need to reach (10,0), (10,2), and (10,6).

• (10,2) is directly triggered by splitter. 0 dominoes.
• (10,0): (9,1)U, (9,0)R = 2 dominoes.
• (10,6): (9,3)D, (9,4)D, (9,5)D, (9,6)R = 4 dominoes. Or with second splitter: (9,3)D, (9,4)Splitter, (9,5)D, (9,6)R = 3 standard + 1 splitter.

Total with 1 splitter: 11 + 0 + 2 + 4 = 17 standard + 1 splitter = 18. Par 16. Total with 2 splitters: 11 + 0 + 2 + 3 = 16 standard + 2 splitter = 18. Par 16.

Still 18 total. Hmm.

Can I shorten the path? What if I place the splitter at (8,2) instead of (9,2)? Path from (0,4) to (8,2): 8 right + 2 up = 10 dominoes. Splitter at (8,2) triggers (9,2), (8,1), (8,3).

• (9,2) needs a domino pointing right to reach (10,2). 1 domino.
• (8,1) up -> (8,0) right -> (9,0) right -> target (10,0). 3 dominoes.
• (8,3) down -> (8,4) right -> (9,4) splitter -> (9,5) down -> (9,6) right -> target (10,6). 3 standard + 1 splitter.

Total: 10 + 1 + 3 + 3 = 17 standard + 2 splitter = 19. Worse.

What if I use the splitter at (9,2) and don't use a second splitter? Path: 11 standard to (9,2). (9,1)U, (9,0)R: 2 standard for (10,0). (9,3)D, (9,4)D, (9,5)D, (9,6)R: 4 standard for (10,6). Total: 11 + 2 + 4 = 17 standard + 1 splitter = 18. Par 16.

Hmm, 18 > 16. I need to either increase the par or redesign the level.

Let me increase the par to 18 for this level. Or I could redesign the level to be more compact.

Actually, let me just increase the par. The par doesn't have to be the absolute minimum - it can be a reasonable target. Let me set par to 18 for level 7.

Wait, but the star system is: 3 stars if totalUsed <= par, 2 stars if <= ceil(par1.2), 1 star otherwise. If par is 18 and the solution uses 18, that's 3 stars. If I set par to 16, the solution uses 18, which is > 16 but <= ceil(161.2)=20, so 2 stars. That's fine too.

Actually, let me just make the levels solvable and set reasonable pars. The par doesn't need to be the absolute minimum - it's a target for 3 stars.

Let me fix the levels:

• Level 5: Change to 1 gap, par 10
• Level 7: Keep as is, par 18 (was 16)
• Level 10: Fix the solution

Level 10: The issue is that the splitter at (6,3) triggers (6,2) UP which is EMPTY. I need a domino at (6,2) pointing UP. And (8,3) splitter triggers (8,4) DOWN which is EMPTY. I need a domino at (8,4) pointing DOWN.

Let me trace the expected solution:

• (0,3)R -> (1,3)R -> (2,3)R -> (3,3)R -> (4,3) Booster -> (6,3)
• (6,3) Splitter right: triggers (7,3)R, (6,2)U, (6,4)D
• (6,2)U -> (6,1)U -> (6,0)R -> target(7,0). Need dominoes at (6,2)U, (6,1)U, (6,0)R.
• (6,4)D -> (6,5)D -> (6,6)D -> (6,7)R -> target(7,7). Need dominoes at (6,4)D, (6,5)D, (6,6)D, (6,7)R.
• (7,3)R -> (8,3) Splitter right: triggers (9,3)R, (8,2)U, (8,4)D
• (8,4)D -> (8,5)R -> target(9,5). Need dominoes at (8,4)D, (8,5)R.

Wait, (8,4) is triggered by both (6,4)D chain and (8,3) splitter. But (6,4)D goes to (6,5)D -> (6,6)D -> (6,7)R. It doesn't go through (8,4).

Let me re-trace:

• (6,3) Splitter triggers: (7,3) right, (6,2) up, (6,4) down
• (6,2) up -> needs domino at (6,2) pointing up -> (6,1) up -> needs domino at (6,1) pointing up -> (6,0) right -> needs domino at (6,0) pointing right -> target (7,0)
• (6,4) down -> needs domino at (6,4) pointing down -> (6,5) down -> needs domino at (6,5) pointing down -> (6,6) down -> needs domino at (6,6) pointing down -> (6,7) right -> needs domino at (6,7) pointing right -> target (7,7)
• (7,3) right -> needs domino at (7,3) pointing right -> (8,3) splitter
• (8,3) Splitter triggers: (9,3) right, (8,2) up, (8,4) down
• (8,4) down -> needs domino at (8,4) pointing down -> (8,5) right -> needs domino at (8,5) pointing right -> target (9,5)

So the full solution: Standard: (1,3)R, (2,3)R, (3,3)R, (6,2)U, (6,1)U, (6,0)R, (6,4)D, (6,5)D, (6,6)D, (6,7)R, (7,3)R, (8,4)D, (8,5)R Splitter: (6,3)R, (8,3)R Booster: (4,3)R

Total: 13 standard + 2 splitter + 1 booster = 16. Budget: 16+2+2=20. Par: 18. Under par!

But in my previous test, I had: Standard: [[1,3,RIGHT],[2,3,RIGHT],[3,3,RIGHT],[6,1,UP],[6,0,RIGHT],[6,4,DOWN],[6,5,DOWN],[6,6,DOWN],[6,7,RIGHT],[7,3,RIGHT],[8,5,RIGHT]]

I was missing (6,2)UP and (8,4)DOWN! That's why it failed. Let me add those.

OK so the fixes are:

1. Level 5: Change grid to have 1 gap instead of 2, keep par at 10
2. Level 7: Change par from 16 to 18 (or find a better solution)
3. Level 10: Add missing dominoes (6,2)UP and (8,4)DOWN

Let me also reconsider Level 7. Can I find a solution with 16 dominoes?

Actually, let me try a different approach for Level 7. What if I use the splitters differently?

Targets: (10,0), (10,2), (10,6). Start: (0,4).

What if I place a splitter at (9,2) pointing right?

• (10,2) target hit directly!
• (9,1) up -> (9,0) right -> target (10,0). 2 dominoes.
• (9,3) down -> (9,4) down -> (9,5) down -> (9,6) right -> target (10,6). 4 dominoes.

Path to (9,2): minimum 11 dominoes (9 right + 2 up from (0,4)).

Total: 11 + 2 + 4 = 17 standard + 1 splitter = 18. Par 16. Over by 2.

What if I use a second splitter at (9,4)?

• (9,3) down -> (9,4) splitter -> (9,5) down -> (9,6) right -> target (10,6). 2 standard + 1 splitter.

Total: 11 + 2 + 2 = 15 standard + 2 splitter = 17. Par 16. Over by 1.

Can I shorten the path? What if I go up first? (0,4)R -> (1,4)U -> (1,3)U -> (1,2)R -> ... -> (9,2) splitter

That's 1 right + 2 up + 8 right = 11 dominoes. Same.

What about going up to row 2 first, then right? (0,4)R -> (0,3)... wait, start is at (0,4) and it points right. So (0,4) falls right -> (1,4). (1,4) up -> (1,3) up -> (1,2) right -> (2,2) right -> ... -> (9,2) splitter

That's 1 + 2 + 8 = 11 dominoes. Same.

The minimum path from (0,4) to (9,2) is 11 steps (Manhattan distance = 9 + 2 = 11). So 11 dominoes minimum.

With 2 splitters, the minimum total is 11 + 2 + 2 = 15 standard + 2 splitter = 17. Still over 16.

I think par 16 is too tight for this level. Let me change it to 18.

Actually, wait. What if I don't go to (9,2)? What if I use a different splitter position?

What if splitter at (10,2) pointing... wait, (10,2) is a target. Can't place domino on target.

What if splitter at (8,2)?

• (9,2) right -> (10,2) target. 1 domino.
• (8,1) up -> (8,0) right -> (9,0) right -> target (10,0). 3 dominoes.
• (8,3) down -> (8,4) right -> (9,4) splitter -> (9,5) down -> (9,6) right -> target (10,6). 3 standard + 1 splitter.

Path to (8,2): 10 dominoes (8 right + 2 up).

Total: 10 + 1 + 3 + 3 = 17 standard + 2 splitter = 19. Worse.

What about splitter at (9,0)?

• (10,0) target hit directly!
• (9,1)... wait, splitter at (9,0) pointing right triggers (10,0), (8,-1) OOB, (9,1) down... wait, (9,1) is down from (9,0)? No, down is (9,1) since DY[DOWN]=1. Yes.
• Actually, splitter at (9,0) pointing right: triggers (10,0) target, (8,0) left, (9,1) down.
• (8,0) left -> (7,0) left -> ... not useful.
• (9,1) down -> (9,2) right -> (10,2) target. 2 dominoes.
• But then how to reach (10,6)? Need to go from (9,2) down to (10,6). That's a long way.

This doesn't seem efficient. Let me just set par to 18 for level 7.

Actually, let me reconsider the level design. Maybe I should make the targets closer together to make the level more solvable at par 16.

Let me redesign Level 7: grid: ['..........T','...........','...........','S..........','...........','...........','..........T','..........T']

Wait, that puts targets at (10,0), (10,6), (10,7). Still far apart.

What about: grid: ['..........T','...........','..........T','...........','S..........','...........','..........T','...........']

This is the current layout. Targets at (10,0), (10,2), (10,6). The issue is that (10,6) is far from (10,2).

What if I move the third target closer? grid: ['..........T','...........','..........T','...........','S..........','..........T','...........','...........']

Targets at (10,0), (10,2), (10,5). Start at (0,4).

Splitter at (9,2) pointing right: triggers (10,2) target, (9,1) up, (9,3) down. (9,1) up -> (9,0) right -> target (10,0). 2 dominoes. (9,3) down -> (9,4) down -> (9,5) - wait, (10,5) is the target, not (9,5). (9,3) down -> (9,4) down -> (9,5) right -> target (10,5). 3 dominoes.

Path to (9,2): 11 dominoes. Total: 11 + 2 + 3 = 16 standard + 1 splitter = 17. Par 16. Over by 1.

With second splitter at (9,4): (9,3) down -> (9,4) splitter -> (9,5) right -> target (10,5). 1 standard + 1 splitter. Total: 11 + 2 + 1 = 14 standard + 2 splitter = 16 = par!

Let me verify: Path: (1,4)R, (2,4)U, (2,3)U, (2,2)R, (3,2)R, (4,2)R, (5,2)R, (6,2)R, (7,2)R, (8,2)R, (9,2) Splitter1 Splitter1 at (9,2) right: triggers (10,2) target, (9,1) up, (9,3) down. (9,1) up -> (9,0) right -> target (10,0). 2 standard. (9,3) down -> (9,4) Splitter2. Splitter2 at (9,4) right: triggers (10,4) - no target, (9,3) already fallen, (9,5) down. (9,5) right -> target (10,5). 1 standard.

Total: 11 + 2 + 1 = 14 standard + 2 splitter = 16 = par!

But wait, (9,5) is down from (9,4)? DY[DOWN] = 1, so (9,4) down -> (9,5). Yes. And (9,5) right -> (10,5) target. Yes!

This works! Let me update Level 7 with this new grid.

Actually, I also need to check: can I place a domino at (9,5)? (9,5) is in row 5 = '..........T'. Position 9 is '.', position 10 is 'T'. So (9,5) is empty and (10,5) is target. Good, I can place a domino at (9,5).

OK so the updated levels are:

• Level 5: 1 gap instead of 2, par 10
• Level 7: Move target from (10,6) to (10,5), par 16
• Level 10: Fix solution (add missing dominoes)

Let me also verify Level 10 with the fixed solution.

For Level 10, the solution should be: Standard: (1,3)R, (2,3)R, (3,3)R, (6,2)U, (6,1)U, (6,0)R, (6,4)D, (6,5)D, (6,6)D, (6,7)R, (7,3)R, (8,4)D, (8,5)R Splitter: (6,3)R, (8,3)R Booster: (4,3)R

Total: 13 standard + 2 splitter + 1 booster = 16. Par 18. Under par, 3 stars!

Let me update the level definitions in the HTML file and verify all levels.