Space Cascade

Cinevva's analyzer read this game's design doc and its source, then wrote the brief below. "Make your own" hands it to the game creator as your opening message, so you start from a real spec rather than a one-line idea.

Create a portrait mobile match-3 puzzle called “Space Cascade.” The game is a single-screen 8x8 celestial-object swap board over a dark animated space background. Keep the play area centered and sized responsively to the available viewport, with a compact HUD above it.

Visual style: the full page is near-black navy (#050816) with large softly blurred drifting nebula gradients—purple/violet toward the upper-left and lower center, cyan/blue toward the upper-right, plus subtle blue-violet haze—and a layer of tiny white, pale-blue, and warm-white stars that slowly drift. Use a clean system sans-serif font. The HUD is horizontally arranged across the top with SCORE on the left and MOVES on the right in small uppercase, letter-spaced muted blue-gray labels, and large bold white values beneath. Put a dark rounded rectangular Undo button in the center, with a thin blue-gray border; it starts disabled and visibly dimmed.

The board is an 8-by-8 grid in a dark slate frame (#1d2436), with approximately 3px gaps, 6px outer padding, and rounded corners around 12px. Each square is a rounded tile (about 8px radius) showing one large centered emoji-like celestial object. Reproduce these five visible tile types and their colored backgrounds: 🚀 rocket on dark blue (#263b63), 🪐 ringed planet on purple (#4b326b), 🌙 crescent moon on brown/olive (#5a4921), ☄️ comet on burnt brown-red (#633526), 🛰️ satellite on teal (#28545a), and 👽 alien on green (#2d5a35). (The supplied implementation uses a random type pool constant of six while defining five styles; for a faithful working recreation, use the six visible symbol styles shown in the reference, or correct the pool to the defined styles rather than creating an unstyled tile.) Tiles should fill the grid cleanly and be large enough to read on a phone.

Core gameplay: initialize a random 8x8 board with no immediate horizontal or vertical runs of three or more, and ensure there is at least one legal move. The player swaps two orthogonally adjacent tiles. Support both touch/mouse interaction modes: tap one tile to select it with a white outline, then tap an adjacent tile to swap; or drag/swipe from a tile and interpret the dominant direction as a one-cell orthogonal swap. Ignore input while animations resolve or after game over. A swap only counts if it creates at least one horizontal or vertical match of three or more, unless one of the swapped tiles is a power tile; otherwise animate/revert the swap without consuming a move.

On a successful swap, save the pre-swap board, score, and move count for the single-use Undo feature, decrement the move counter, then resolve all matches. Matches are contiguous runs of three or more identical base objects, found horizontally and vertically. Clear every cell in all matched groups, counting overlapping horizontal/vertical cells only once. Animate clearing tiles by fading them out and scaling them up briefly. Award 10 points per distinct cleared tile multiplied by the cascade chain number (first wave x1, second wave x2, etc.). After clearing, let tiles fall vertically under gravity, then spawn random new objects into empty cells at the top, and continue resolving any new matches until stable. Animate the tile changes/falling with short roughly 200ms transitions.

Power tiles: when a matched line has four or more objects, retain one middle cell from that group as a power tile instead of clearing it. Mark it with a bright yellow outline, yellow glow, pulsing animation, and a small yellow ✦ badge near its top-right corner. Give each spawned power tile an extra 50 points multiplied by the current cascade chain. A power tile may be swapped as a special move even when the swap creates no normal match; when a swapped power tile detonates, clear its entire row and entire column, then apply gravity, refill, and normal cascade resolution. Power tiles also count as their base object for matching. Maintain the implementation behavior that a power tile is represented as its base type plus 10 internally.

The initial state should show Score 0 and Moves 20. Each valid move consumes one move; an invalid swap does not. The Undo button becomes enabled after a successful move and restores the saved board, score, and moves exactly once, then disables itself. It cannot be used while an animation is running or after game over. If the board ever has no legal swap, automatically generate a fresh solvable board. When moves reach zero after resolution, stop interaction and display a dark translucent rounded game-over overlay over the board with “Game Over,” “Final score: [score],” and a prominent blue rounded “Play Again” button. Restart resets score to zero, moves to 20, clears undo state, and creates a fresh solvable board. Use subtle selected outlines, fade/scale clearing animation, pulsing power glow, and the animated stars/nebula to provide the cascade feel without adding extra screens, levels, lives, timers, sound, or mechanics not present in the reference.