Tech Diagram

:root {
  /* Dark mode (default canvas) */
  --bg-deep: #0d1117;
  --bg-surface: #161b22;
  --bg-elevated: #21262d;
  --border-subtle: rgba(240, 246, 252, 0.1);
  --text-bright: #f0f6fc;
  --text-secondary: #8b949e;
  --text-muted: #6e7681;

  /* Accent palette */
  --accent-blue: #58a6ff;
  --accent-green: #3fb950;
  --accent-purple: #bc8cff;
  --accent-orange: #d29922;
  --accent-red: #f85149;
  --accent-cyan: #39d2c0;
  --accent-pink: #f778ba;

  /* Light mode (optional, for embedded diagrams) */
  --bg-light: #ffffff;
  --bg-light-surface: #f6f8fa;
  --text-light-primary: #1f2328;
  --text-light-secondary: #656d76;
}

Color Rules

• Dark mode is default for all diagrams
• Each pipeline stage or layer gets a distinct accent color
• Use --text-secondary for labels and annotations
• Use --border-subtle for connecting lines and borders
• Semantic colors: green = healthy/success, red = error/alert, orange = warning

Typography

Canvas

Width:  1200px (default, responsive down to 800px)
Height: auto (content-driven)
Padding: 48px

Component Library

Pipeline Flow

Horizontal or vertical sequence of stages with connecting arrows. Each stage has an icon area, label, and description.

Layer/Stack Diagram

Vertical stack of labeled layers with optional descriptions. Top = highest abstraction, bottom = lowest.

Component Diagram

Grid or freeform layout of service boxes with connection lines. Each component shows name, tech, and status.

Before/After Split

Side-by-side comparison with a vertical divider. Left = before state, right = after state.

Timeline

Horizontal or vertical sequence of milestones with dates, descriptions, and status indicators.

Metric Callout Row

Horizontal row of KPI cards with large numbers, labels, and optional trend indicators.

Key Principles

1. One concept per diagram. If it needs two diagrams, make two files.
2. Labels on everything. Every box, arrow, and region should be labeled.
3. Consistent spacing. Use CSS grid or flexbox, not absolute positioning.
4. No external deps. Everything inline — CSS in <style>, icons as inline SVG.
5. Print-friendly. Include @media print with light background override.

Anti-Patterns

• No raster images (PNG/JPG) — use inline SVG for all icons
• No external CSS/JS — everything embedded
• No gradients as primary fill — use flat colors with subtle borders
• No more than 8 items in a single row — wrap or use grid
• No decorative elements that do not convey information

File Conventions

• Filename: {project}-{diagram-type}.html (e.g., pipeline-architecture.html)
• Single file: All CSS inline in <style>, all SVG inline
• Responsive: Works at 800-1400px width range

For complete HTML/CSS patterns and full examples, see REFERENCE.md.