Flipwing

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-friendly 2D arcade endless game titled “Flipwing,” rendered on a full-screen HTML canvas with a responsive viewport and a clean, polished flat/vector style. The game is a Flappy Bird-like side-scroller, but the main mechanic is flipping gravity: the small round orange-yellow bird stays around 28% of the screen width while obstacle gates move from right to left. On the ready screen, show a dark translucent rounded panel centered on the playfield with the title “FLIPWING,” the instructions “Tap to flip gravity” and “Thread the moving gates,” and an orange rounded “START FLYING” button. A pointer/tap starts the game; subsequent pointer taps flip gravity. Also support Space and ArrowUp as the same action.

The playfield should have a vertical blue atmospheric gradient background, darkest navy at the top and lighter teal-blue toward the bottom, with a subtle warm radial glow near the upper-right area. Add several very faint, soft pale clouds drifting slowly horizontally, and a darker translucent strip along the bottom edge. Keep the camera fixed in a side view with no scrolling world camera; only the gates move left.

The player is a cute stylized circular bird at about 28% screen width and initially centered vertically. Draw its body as a glowing radial-gradient circle, pale yellow in the center and orange at the edges, with a white eye and dark navy pupil, a small pale-yellow triangular beak pointing right, and a triangular rear wing/tail accent. The rear accent changes color to cyan while gravity is inverted/ceiling mode and red-orange while normal/floor mode. Slightly rotate the bird based on its vertical velocity, clamped to a modest angle. Emit a short trail of small colored particles whenever gravity is flipped, and a larger burst on collision; include a brief white flash on every flip and light screen shake when crashing.

Use simple gravity physics: normal gravity accelerates the bird downward, while inverted gravity accelerates it upward toward the ceiling. Each tap reverses the gravity direction and gives the bird an immediate vertical impulse away from the current surface: in floor mode, a flip launches upward; in ceiling mode, a flip launches downward. The bird has a circular collision radius. It dies if it touches the top or bottom screen boundary, or if it overlaps an obstacle gate.

Continuously spawn pairs of solid vertical gates at the right edge and move them left. Each gate is a vertical column split into a top section and bottom section with a clear gap between them; the bird must pass through the gap. Use a gate width of about 66 pixels plus slightly wider horizontal cap pieces extending about 7 pixels on each side at both ends of the gap. Gates should have a dark saturated column body, bright colored cap bars, and a narrow translucent highlight stripe. Alternate the vertical placement tendency of successive gaps: one gap can be broadly randomized within safe margins, the next should tend toward the upper portion, then alternate again. Keep a minimum safe margin of roughly 80 pixels from the screen edges. Start with a gap around 23% of screen height, never smaller than about 138 pixels, and gradually narrow it as score increases. Gate speed begins around 190 pixels/second and rises with score up to roughly 310 pixels/second; spawn intervals begin around 1.65 seconds and shorten modestly with score but do not go below about 1.15 seconds. Randomly color each gate cyan/teal or warm yellow-orange: cyan gates use a dark teal body and bright turquoise caps; warm gates use a dark burnt-orange body and bright golden caps.

Award one point whenever a gate’s right edge passes the bird. There are no lives, ammo, powerups, or enemies beyond the moving gates. Display a HUD throughout: at top center, show the current score as a large cream-colored number with a subtle shadow; at top right, show “BEST N” in bold translucent white, persisting the best score locally between runs; at top left, show either “FLOOR MODE” or “CEILING MODE” in bold light text and a short underline bar colored warm yellow in floor mode or cyan in ceiling mode. On the ready screen, the HUD and the stationary bird/scene may remain visible behind the panel.

When the bird collides or reaches a boundary, stop gameplay, save/update the best score, and show a centered dark translucent rounded game-over panel with the title “CRASHED,” a line reading “Score N  •  Best N,” the instruction “Tap to try another run,” and an orange rounded “FLY AGAIN” button. A tap, Space, or ArrowUp from the ready or game-over state should reset score and obstacles and begin a new run immediately with an initial gravity flip. Keep the visual language consistent: navy/blue atmosphere, cream HUD typography, cyan and golden-orange accents, rounded panels, subtle shadows, particles, and restrained screen effects.