# Layerline — Art Bible v0.1

**Status:** provisional reference set complete; production lock requires prototype greenlight

## North star

Layerline looks like a quiet handheld logic instrument. Matte shutters float over a deep navy well;
bold traces make electrical consequences readable at phone size. The visual identity comes from
layered hinged geometry plus live mint flow—not from a circuit theme applied to a familiar grid.

The authoritative rules are `gdd.md`, `ux-flow.md`, and `visual-brief.md`. Generated images may
interpret those rules but cannot add mechanics, screens, rewards, characters, or content families.

## Gameplay frame

- Fixed orthographic portrait view; board centered in the safe area.
- Layer order: night field -> board well -> fixed backplane -> shutters/shadows -> traces -> preview
  and live flow -> board UI -> modal UI.
- The active hinge tab, occupied footprint, cover relationships, source, and every required terminal
  must remain visible or deliberately indicated.
- A preview must distinguish current state, future footprint, newly covered/exposed objects, and
  future power without relying only on color.

## Component language

| Component | Normal | Preview/active | Blocked/completed |
|---|---|---|---|
| Shutter | cool or slate matte face, ink trace | blue ghost edge and lifted shadow | recessed/dim when covered |
| Hinge tab | integrated pill with face glyph | warm-white outline | coral pulse on illegal touch |
| Source | mint ring with directional notch | prospective path dashed | steady halo when connected |
| Terminal | amber hollow socket + unique shape | blue outer prediction ring | amber fill plus mint center when powered |
| Trace | ink monoline | blue dashed future line | mint live line with weight increase |
| Diode | triangle + stop bar in trace | direction preserved in preview | never color-only |
| Bridge | small overpass gap in one line | both channels independently previewed | no connection dot |
| Relay | outlined gate + hinge glyph | mint fill when enabled | recessed while unpowered |

## Environment and chapters

The background remains one night-field family. Modules change only restrained board-well accents,
trace symbols, and rule illustrations; they do not reskin the game into unrelated worlds. Decorative
marks stay outside playable footprints and never resemble usable ports.

## UI system

- Home: logo mark derived from two overlapping shutters and one continuous live line; one primary
  Continue/Start button.
- Chapter Map: vertical sequence of eight labeled modules using rule icons, not scenic islands.
- Playing: compact top label; bottom controls for undo, restart, and pause; no currencies or banners.
- Modals: opaque navy panels, warm-white labels, one mint primary action, one outline secondary.
- Minimum touch target 44 x 44 CSS pixels; safe area required on all sides.

## Typography, iconography, and localization

Choose a licensed geometric humanist sans during production. Reference images use placeholder
letterforms only. Layout must tolerate 30% longer labels and dynamic type on non-board screens.
Icons use rounded strokes, consistent optical weight, and platform accessibility labels.

## Motion, light, and audio pairing

Motion follows the exact state reducer: preview, commit, flow recompute, completion. Shadows may
communicate layer order but never imply free 3D rotation. Mint bloom is limited to powered traces;
preview blue never appears as a committed state. Sound events map one-to-one to preview cancel,
legal flip, illegal touch, power connect, undo, and completion.

## Accessibility variants

- Standard and high-contrast palettes preserve semantic roles.
- Channels combine hue with solid/dashed/double-line patterns and socket geometry.
- Reduced-motion reference replaces hinge animation and chase with crossfades and static outlines.
- No gameplay information may depend on glow, depth shadow, audio, or haptics alone.

## Technical export rules

- Reference boards: PNG, 1536 x 2732 or nearest GPT Image 2 portrait output, sRGB, opaque.
- Production sprites: lossless PNG, power-of-two atlases where useful, 2x mobile reference density.
- UI text and numerals remain live text; never ship generated raster text.
- Nine-slice panels preserve corner radius and border weight.
- VFX colors come from tokens; no per-level embedded color edits.

## Forbidden drift

No paper/origami finish, screw/bolt hardware, tray sorting, picture reveal, independent grid-tile
rotation, botanical restoration, isometric factory, neon cyberpunk density, realistic PCB, coins,
stars, loot, characters, or generated fake store badges.

## Reference status

Three GPT Image 2 references exist and passed visual inspection on 2026-08-08. The master passed on
its first render. The world sheet was edited once to remove a fastener-like hinge detail. The UI
frame was edited once to replace a generic pipe-tile grid with the authoritative layered-shutter
topology. The manifest preserves the final prompts, references, outputs, and QA decisions.