Dither

# Dither

## Philosophy

Dither renders any interface through a low-resolution CGA phosphor grid. Every module is a framed utility window snapped to an 8-pixel rhythm; surfaces carry an ordered checker-dither and fixed scanlines so flat colour reads like it is drawn through a CRT; feedback appears as inverse-video labels, segmented meters, and blinking machine states. It keeps the retro home-computer shell identity while correcting the craft to current standards.

### Values

- Respect a limited palette and let colour coding carry system meaning - green runs the system, cyan carries signal, magenta marks memory.
- Build hierarchy through framed windows, inverse-video title bars, and dense monospace labels.
- Preserve pixel alignment so borders, bevels, and dither read crisply at every size.
- Use machine-like feedback: segmented meters, status lamps, and stepped state changes.
- Pair nostalgia with utility - the interface stays genuinely usable, not costume.

### Anti-Values

- Soft neumorphic depth, blur, and frosted glass.
- Rounded organic cards, pills, or amorphous panels.
- Palette sprawl beyond the intentional phosphor set.
- Airy luxury spacing that erases the compact workstation feel.
- Illustrative decoration that overwhelms the functional screen structure.

### Visual Character

- Every window and key wears a full four-sided pixel bevel: a bright top-left highlight edge and a dark bottom-right shadow edge, recreating the embossed frames of DOS and 8-bit GUI shells.
- Backgrounds carry repeating scanlines and a checker-dither field so flat colour feels rendered through a low-resolution CRT.
- Typography pairs a bitmap display face (Press Start 2P) with dense monospace data text (VT323, IBM Plex Mono), using uppercase labels, inverse-video chips, and wide tracking.
- Interactive controls are rectangular, radius-0 keys with a stepped hard-black shadow and discrete on/off status lamps - never soft pills or floating modern buttons.
- Information is arranged as tiled utility windows, instrument bays, and ledger lists on an 8px grid, producing the compact rectangular rhythm of file managers and BBS dashboards.

## Tokens

### Colors

| Name | Value |
|------|-------|
| bg | `#0A0A0A` |
| surface | `#161616` |
| surface_solid | `#1E1E1E` |
| text | `#F2F2F2` |
| muted | `#9AA39A` |
| border | `#3A3F3A` |
| accent | `#55FF55` |
| accent_2 | `#55FFFF` |
| accent_soft | `#FF55FF` |
| on_accent | `#0A0A0A` |
| success | `#55FF55` |
| warning | `#FFF255` |
| error | `#FF5A5A` |
| info | `#55FFFF` |

### Typography

- **Base Size**: 17px
- **Body Font**: 'VT323', monospace
- **Heading Font**: 'Press Start 2P', monospace
- **Mono Font**: 'IBM Plex Mono', monospace
- **Heading Weight**: 400
- **Heading Transform**: uppercase
- **Letter Spacing**: 0.04em
- **Line Height**: 1.5
- **Scale Ratio**: 1.25
- **Google Fonts Url**: https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;500;600;700&family=Press+Start+2P&family=VT323&display=swap

### Radii

- **None**: 0px
- **Md**: 16px
- **Lg**: 24px
- **Full**: 9999px

### Shadows

- **Sm**: 2px 2px 0 #000000
- **Md**: 4px 4px 0 #000000
- **Lg**: 6px 6px 0 #000000

### Spacing

- **Base**: 8px
- **Scale**: 1.5

### Surfaces

- **Treatment**: CRT phosphor: repeating horizontal scanlines plus an ordered checker-dither field over dark panels, dual-edge pixel bevel framing (bright top-left, dark bottom-right).
- **Card Style**: Framed utility windows with an inverse-video title bar, hard 90-degree corners, and a stepped hard-black drop shadow.
- **Bg Pattern**: scanlines + checker-dither

### Borders

- **Default Width**: 2px
- **Accent Width**: 2px
- **Style**: solid
- **Character**: Full four-sided pixel bevel: a bright top-left highlight edge and a dark bottom-right shadow edge on every window and key, recreating DOS/8-bit GUI shell frames.

### Motion

- **Duration**: 120ms
- **Easing**: steps(3, end)
- **Philosophy**: Snappy, quantized machine motion: state changes step rather than glide; a cursor blink and a scanline sweep are the only ambient motion.

## Rules

### Composition

Compose screens as nested utility windows: a command/status bar at the top, a primary work surface in the centre, and supporting instrument panels flanking it. Modules align to the 8px grid and behave like rearrangeable software panes rather than marketing cards.

### Hierarchy

Title bars, inverse labels, colour-state chips, and boxed readouts define hierarchy. Large type is reserved for screen titles and critical counters; most hierarchy comes from framing, fill contrast, and status-colour changes.

### Density

Compact and information-rich - controls sit close, lists are multi-row, and readouts expose many simultaneous states, with density balanced across the canvas (never a crowded cluster beside a starved void).

### Signature Patterns

- Repeating-linear-gradient scanlines plus a checker-dither field on major surfaces, page-wide, so panels visibly emulate CRT phosphor texture and limited-colour shading.
- Dual-edge pixel framing on every window and key: a bright top-left border and a dark bottom-right border for the stepped bevel of DOS and 8-bit GUI shells.
- Inverse-video title bars and status chips with uppercase mono typography, where labels sit inside framed rectangles instead of floating above content.
- Meters and charts built from discrete rectangular cells rather than smooth bars, making progress, memory, and signal read as quantized and machine-like.
- Recurring corner checker-pixels and hard 90-degree geometry so the interface never reads as a generic modern dashboard with a retro palette pasted on top.

### Links Motion

Links carry the language's own gesture - an inverse-video ink-up that fills the accent on hover, never a bare default underline. Motion is snappy and quantized (steps()); the settled, fully-rendered state is the no-JS default and reveal motion is added on top behind a class the inline script sets. prefers-reduced-motion is respected.

## Layout

### Grid

A rigid 12-column desktop grid on an 8px base unit; panels snap to whole-column spans and all internal spacing resolves in multiples of 4px or 8px.

### Breakpoints

The tablet band (~768-1024) is its own considered two-column layout with full-width title bars preserved - never a mobile column stretched wide. At mobile (~390px) it collapses to a single column: nav wraps or collapses, oversized headlines shrink and wrap, and data tables scroll horizontally only where necessary.

### Whitespace

Whitespace is economical and structural - gaps separate windows and control groups, but empty space never overpowers the dense workstation character.

## Guidance

### Do

- Use the phosphor palette intentionally - green system, cyan signal, magenta memory.
- Snap icons, borders, and layout edges to pixel-friendly values so the interface stays crisp.
- Prefer framed windows, title bars, meter blocks, and ledger lists over floating cards.
- Use the display / body / mono pairing to clearly distinguish headings from data text.
- Run scanline and dither texture across large surfaces to keep the scene materially retro.

### Don't

- Introduce blur, translucent glass, or soft radial lighting.
- Use rounded corners, pills, or amorphous panels.
- Rely on smooth modern charts or gradients when segmented cells express the same state.
- Let whitespace become sparse luxury minimalism, or let control labels wrap.
- Mix glossy 3D or photographic imagery into the workstation scene - imagery stays in the paired pixel-art / CRT-dither technique.

## Imagery Direction

### Pairs With

dither-phosphor

### Technique

Low-resolution CGA-era pixel art: flat quantized colour shaded by ordered checker-dither, hard pixel/voxel forms, a fixed horizontal scanline overlay, and a phosphor bloom on the brightest cells against a near-black ground.

### Usage

One full-bleed dithered hero scene at the top of the landing (a CGA voxel terrain); feature imagery kept on its own ground beside copy, never under text. All imagery in the same pixel-dither technique - never glossy 3D or photographic.

### Hero File Id

fl-019f3dba-9513-7581-b0d2-1444f302793f

---
version: "alpha"
name: "Dither"
description: "Agent-curated design language exported from Katagami as DESIGN.md."
colors:
  bg: "#0A0A0A"
  surface: "#161616"
  surface_solid: "#1E1E1E"
  text: "#F2F2F2"
  muted: "#9AA39A"
  border: "#3A3F3A"
  accent: "#55FF55"
  accent_2: "#55FFFF"
  accent_soft: "#FF55FF"
  on_accent: "#0A0A0A"
  success: "#55FF55"
  warning: "#FFF255"
  error: "#FF5A5A"
  info: "#55FFFF"
typography:
  headline-lg:
    fontFamily: "'Press Start 2P', monospace"
    fontSize: "2.075rem"
    fontWeight: 700
    lineHeight: 1.1
    letterSpacing: "0.04em"
  headline-md:
    fontFamily: "'Press Start 2P', monospace"
    fontSize: "1.66rem"
    fontWeight: 600
    lineHeight: 1.15
    letterSpacing: "0.04em"
  body-md:
    fontFamily: "'VT323', monospace"
    fontSize: "17px"
    fontWeight: 400
    lineHeight: 1.5
    letterSpacing: "0.04em"
  label-md:
    fontFamily: "'IBM Plex Mono', monospace"
    fontSize: "0.75rem"
    fontWeight: 600
    lineHeight: 1
    letterSpacing: "0.08em"
rounded:
  none: "0px"
  md: "16px"
  lg: "24px"
  full: "9999px"
spacing:
  base: "8px"
components:
  color-reference-bg:
    backgroundColor: "{colors.bg}"
  color-reference-surface:
    backgroundColor: "{colors.surface}"
  color-reference-surface_solid:
    backgroundColor: "{colors.surface_solid}"
  color-reference-text:
    backgroundColor: "{colors.text}"
  color-reference-muted:
    backgroundColor: "{colors.muted}"
  color-reference-border:
    backgroundColor: "{colors.border}"
  color-reference-accent:
    backgroundColor: "{colors.accent}"
  color-reference-accent_2:
    backgroundColor: "{colors.accent_2}"
  color-reference-accent_soft:
    backgroundColor: "{colors.accent_soft}"
  color-reference-on_accent:
    backgroundColor: "{colors.on_accent}"
  color-reference-success:
    backgroundColor: "{colors.success}"
  color-reference-warning:
    backgroundColor: "{colors.warning}"
  color-reference-error:
    backgroundColor: "{colors.error}"
  color-reference-info:
    backgroundColor: "{colors.info}"
  button-primary:
    backgroundColor: "{colors.accent}"
    textColor: "#000000"
    typography: "{typography.label-md}"
    rounded: "{rounded.md}"
    padding: "{spacing.base}"
  card-surface:
    backgroundColor: "{colors.surface}"
    textColor: "{colors.text}"
    rounded: "{rounded.md}"
    padding: "{spacing.base}"
  input-default:
    backgroundColor: "{colors.surface}"
    textColor: "{colors.text}"
    rounded: "{rounded.md}"
    height: "44px"
---

# Dither

## Overview

Dither renders any interface through a low-resolution CGA phosphor grid. Every module is a framed utility window snapped to an 8-pixel rhythm; surfaces carry an ordered checker-dither and fixed scanlines so flat colour reads like it is drawn through a CRT; feedback appears as inverse-video labels, segmented meters, and blinking machine states. It keeps the retro home-computer shell identity while correcting the craft to current standards.

### Values

- Respect a limited palette and let colour coding carry system meaning - green runs the system, cyan carries signal, magenta marks memory.
- Build hierarchy through framed windows, inverse-video title bars, and dense monospace labels.
- Preserve pixel alignment so borders, bevels, and dither read crisply at every size.
- Use machine-like feedback: segmented meters, status lamps, and stepped state changes.
- Pair nostalgia with utility - the interface stays genuinely usable, not costume.

### Anti-Values

- Soft neumorphic depth, blur, and frosted glass.
- Rounded organic cards, pills, or amorphous panels.
- Palette sprawl beyond the intentional phosphor set.
- Airy luxury spacing that erases the compact workstation feel.
- Illustrative decoration that overwhelms the functional screen structure.

### Visual Character

- Every window and key wears a full four-sided pixel bevel: a bright top-left highlight edge and a dark bottom-right shadow edge, recreating the embossed frames of DOS and 8-bit GUI shells.
- Backgrounds carry repeating scanlines and a checker-dither field so flat colour feels rendered through a low-resolution CRT.
- Typography pairs a bitmap display face (Press Start 2P) with dense monospace data text (VT323, IBM Plex Mono), using uppercase labels, inverse-video chips, and wide tracking.
- Interactive controls are rectangular, radius-0 keys with a stepped hard-black shadow and discrete on/off status lamps - never soft pills or floating modern buttons.
- Information is arranged as tiled utility windows, instrument bays, and ledger lists on an 8px grid, producing the compact rectangular rhythm of file managers and BBS dashboards.

## Colors

Use the YAML color tokens as the normative palette. The prose below names the roles agents should preserve when generating UI.

| Token | Value |
|-------|-------|
| bg | `#0A0A0A` |
| surface | `#161616` |
| surface_solid | `#1E1E1E` |
| text | `#F2F2F2` |
| muted | `#9AA39A` |
| border | `#3A3F3A` |
| accent | `#55FF55` |
| accent_2 | `#55FFFF` |
| accent_soft | `#FF55FF` |
| on_accent | `#0A0A0A` |
| success | `#55FF55` |
| warning | `#FFF255` |
| error | `#FF5A5A` |
| info | `#55FFFF` |

## Typography

- **Headline-Lg**: 'Press Start 2P', monospace, 2.075rem, weight 700, line-height 1.1.
- **Headline-Md**: 'Press Start 2P', monospace, 1.66rem, weight 600, line-height 1.15.
- **Body-Md**: 'VT323', monospace, 17px, weight 400, line-height 1.5.
- **Label-Md**: 'IBM Plex Mono', monospace, 0.75rem, weight 600, line-height 1.

## Layout

### Spacing Tokens

- **Base**: `8px`

### Grid

A rigid 12-column desktop grid on an 8px base unit; panels snap to whole-column spans and all internal spacing resolves in multiples of 4px or 8px.

### Breakpoints

The tablet band (~768-1024) is its own considered two-column layout with full-width title bars preserved - never a mobile column stretched wide. At mobile (~390px) it collapses to a single column: nav wraps or collapses, oversized headlines shrink and wrap, and data tables scroll horizontally only where necessary.

### Whitespace

Whitespace is economical and structural - gaps separate windows and control groups, but empty space never overpowers the dense workstation character.

## Elevation & Depth

### Shadows

- **Sm**: 2px 2px 0 #000000
- **Md**: 4px 4px 0 #000000
- **Lg**: 6px 6px 0 #000000

## Shapes

### Rounded

- **None**: `0px`
- **Md**: `16px`
- **Lg**: `24px`
- **Full**: `9999px`

### Surfaces

- **Treatment**: CRT phosphor: repeating horizontal scanlines plus an ordered checker-dither field over dark panels, dual-edge pixel bevel framing (bright top-left, dark bottom-right).
- **Card Style**: Framed utility windows with an inverse-video title bar, hard 90-degree corners, and a stepped hard-black drop shadow.
- **Bg Pattern**: scanlines + checker-dither

### Borders

- **Default Width**: 2px
- **Accent Width**: 2px
- **Style**: solid
- **Character**: Full four-sided pixel bevel: a bright top-left highlight edge and a dark bottom-right shadow edge on every window and key, recreating DOS/8-bit GUI shell frames.

## Components

### Composition

Compose screens as nested utility windows: a command/status bar at the top, a primary work surface in the centre, and supporting instrument panels flanking it. Modules align to the 8px grid and behave like rearrangeable software panes rather than marketing cards.

### Hierarchy

Title bars, inverse labels, colour-state chips, and boxed readouts define hierarchy. Large type is reserved for screen titles and critical counters; most hierarchy comes from framing, fill contrast, and status-colour changes.

### Density

Compact and information-rich - controls sit close, lists are multi-row, and readouts expose many simultaneous states, with density balanced across the canvas (never a crowded cluster beside a starved void).

### Signature Patterns

- Repeating-linear-gradient scanlines plus a checker-dither field on major surfaces, page-wide, so panels visibly emulate CRT phosphor texture and limited-colour shading.
- Dual-edge pixel framing on every window and key: a bright top-left border and a dark bottom-right border for the stepped bevel of DOS and 8-bit GUI shells.
- Inverse-video title bars and status chips with uppercase mono typography, where labels sit inside framed rectangles instead of floating above content.
- Meters and charts built from discrete rectangular cells rather than smooth bars, making progress, memory, and signal read as quantized and machine-like.
- Recurring corner checker-pixels and hard 90-degree geometry so the interface never reads as a generic modern dashboard with a retro palette pasted on top.

### Links Motion

Links carry the language's own gesture - an inverse-video ink-up that fills the accent on hover, never a bare default underline. Motion is snappy and quantized (steps()); the settled, fully-rendered state is the no-JS default and reveal motion is added on top behind a class the inline script sets. prefers-reduced-motion is respected.

## shadcn/ui Usage

When the target app uses shadcn/ui, copy DESIGN.md with shadcn instead of the plain DESIGN.md. It contains the same Katagami design-language source plus the shadcn/ui primitives, imports, theme variables, component recipes, and preview-shot guidance.

DESIGN.md with shadcn: `/language/en-019f3dc1-daa0-7132-b782-52468ebdfb94/DESIGN.with-shadcn.md`.

The shadcn page also exposes optional machine-readable files for automation, but the human-facing handoff is DESIGN.md with shadcn.

Install recommended primitives with `npx shadcn@latest add button card input textarea select dialog sheet tabs badge separator checkbox switch slider tooltip dropdown-menu table`.

Use these primitives in shadcn apps:
- button
- card
- input
- textarea
- select
- dialog
- sheet
- tabs
- badge
- separator
- checkbox
- switch
- slider
- tooltip
- dropdown-menu
- table

Implementation rule for agents: import shadcn primitives from `@/components/ui/*`, apply the generated CSS variables first, then compose the language-specific recipes from the companion MD. Katagami remains the source of truth; shadcn names are the implementation surface.

## Do's and Don'ts

- Do Use the phosphor palette intentionally - green system, cyan signal, magenta memory.
- Do Snap icons, borders, and layout edges to pixel-friendly values so the interface stays crisp.
- Do Prefer framed windows, title bars, meter blocks, and ledger lists over floating cards.
- Do Use the display / body / mono pairing to clearly distinguish headings from data text.
- Do Run scanline and dither texture across large surfaces to keep the scene materially retro.
- Don't Introduce blur, translucent glass, or soft radial lighting.
- Don't Use rounded corners, pills, or amorphous panels.
- Don't Rely on smooth modern charts or gradients when segmented cells express the same state.
- Don't Let whitespace become sparse luxury minimalism, or let control labels wrap.
- Don't Mix glossy 3D or photographic imagery into the workstation scene - imagery stays in the paired pixel-art / CRT-dither technique.

## Imagery Direction

### Pairs With

dither-phosphor

### Technique

Low-resolution CGA-era pixel art: flat quantized colour shaded by ordered checker-dither, hard pixel/voxel forms, a fixed horizontal scanline overlay, and a phosphor bloom on the brightest cells against a near-black ground.

### Usage

One full-bleed dithered hero scene at the top of the landing (a CGA voxel terrain); feature imagery kept on its own ground beside copy, never under text. All imagery in the same pixel-dither technique - never glossy 3D or photographic.

### Hero File Id

fl-019f3dba-9513-7581-b0d2-1444f302793f

```json
{
  "$schema": "https://ui.shadcn.com/schema/registry-item.json",
  "name": "dither",
  "type": "registry:theme",
  "title": "Dither shadcn Theme",
  "cssVars": {
    "theme": {},
    "light": {
      "background": "#0A0A0A",
      "foreground": "#F2F2F2",
      "card": "#161616",
      "card-foreground": "#F2F2F2",
      "popover": "#161616",
      "popover-foreground": "#F2F2F2",
      "primary": "#F2F2F2",
      "primary-foreground": "#111111",
      "secondary": "#f4f4f5",
      "secondary-foreground": "#111111",
      "muted": "#9AA39A",
      "muted-foreground": "#F2F2F2",
      "accent": "#55FF55",
      "accent-foreground": "#111111",
      "destructive": "#FF5A5A",
      "border": "#3A3F3A",
      "input": "#3A3F3A",
      "ring": "#55FF55",
      "chart-1": "#F2F2F2",
      "chart-2": "#f4f4f5",
      "chart-3": "#55FF55",
      "chart-4": "#55FF55",
      "chart-5": "#FFF255",
      "sidebar": "#161616",
      "sidebar-foreground": "#F2F2F2",
      "sidebar-primary": "#F2F2F2",
      "sidebar-primary-foreground": "#111111",
      "sidebar-accent": "#55FFFF",
      "sidebar-accent-foreground": "#111111",
      "sidebar-border": "#3A3F3A",
      "sidebar-ring": "#55FF55",
      "radius": "16px"
    },
    "dark": {
      "background": "#0f1115",
      "foreground": "#f8fafc",
      "card": "#181b22",
      "card-foreground": "#f8fafc",
      "popover": "#181b22",
      "popover-foreground": "#f8fafc",
      "primary": "#F2F2F2",
      "primary-foreground": "#111111",
      "secondary": "#252a33",
      "secondary-foreground": "#f8fafc",
      "muted": "#252a33",
      "muted-foreground": "#a1a1aa",
      "accent": "#55FF55",
      "accent-foreground": "#111111",
      "destructive": "#FF5A5A",
      "border": "#303642",
      "input": "#303642",
      "ring": "#55FF55",
      "chart-1": "#F2F2F2",
      "chart-2": "#f4f4f5",
      "chart-3": "#55FF55",
      "chart-4": "#55FF55",
      "chart-5": "#FFF255",
      "sidebar": "#181b22",
      "sidebar-foreground": "#f8fafc",
      "sidebar-primary": "#F2F2F2",
      "sidebar-primary-foreground": "#111111",
      "sidebar-accent": "#55FF55",
      "sidebar-accent-foreground": "#111111",
      "sidebar-border": "#303642",
      "sidebar-ring": "#55FF55",
      "radius": "16px"
    }
  },
  "meta": {
    "source": "katagami",
    "languageId": "en-019f3dc1-daa0-7132-b782-52468ebdfb94",
    "slug": "dither",
    "componentManifest": [
      "button",
      "card",
      "input",
      "textarea",
      "select",
      "dialog",
      "sheet",
      "tabs",
      "badge",
      "separator",
      "checkbox",
      "switch",
      "slider",
      "tooltip",
      "dropdown-menu",
      "table"
    ],
    "installCommand": "npx shadcn@latest add button card input textarea select dialog sheet tabs badge separator checkbox switch slider tooltip dropdown-menu table",
    "nativeTokenNames": {
      "colors": [
        "accent",
        "accent_2",
        "accent_soft",
        "bg",
        "border",
        "error",
        "info",
        "muted",
        "on_accent",
        "success",
        "surface",
        "surface_solid",
        "text",
        "warning"
      ],
      "typography": [
        "base_size",
        "body_font",
        "google_fonts_url",
        "heading_font",
        "heading_transform",
        "heading_weight",
        "letter_spacing",
        "line_height",
        "mono_font",
        "scale_ratio"
      ],
      "radii": [
        "full",
        "lg",
        "md",
        "none"
      ],
      "shadows": [
        "lg",
        "md",
        "sm"
      ],
      "spacing": [
        "base",
        "scale"
      ],
      "surfaces": [
        "bg_pattern",
        "card_style",
        "treatment"
      ],
      "borders": [
        "accent_width",
        "character",
        "default_width",
        "style"
      ],
      "motion": [
        "duration",
        "easing",
        "philosophy"
      ]
    }
  }
}
```