Generate professional, dark-themed technical architecture diagrams as standalone HTML files with inline SVG graphics. No external tools, no API keys, no rendering libraries — just write the HTML file and open it in a browser.
## Scope
**Best suited for:**
- Software system architecture (frontend / backend / database layers)
- Animated explainers (consider an animation skill)
If a more specialized skill is available for the subject, prefer that. If none fits, this skill can also serve as a general SVG diagram fallback — the output will just carry the dark tech aesthetic described below.
Based on [Cocoon AI's architecture-diagram-generator](https://github.com/Cocoon-AI/architecture-diagram-generator) (MIT).
## Workflow
1. User describes their system architecture (components, connections, technologies)
2. Generate the HTML file following the design system below
3. Save with `write_file` to a `.html` file (e.g. `~/architecture-diagram.html`)
4. User opens in any browser — works offline, no dependencies
### Output Location
Save diagrams to a user-specified path, or default to the current working directory:
```
./[project-name]-architecture.html
```
### Preview
After saving, suggest the user open it:
```bash
# macOS
open ./my-architecture.html
# Linux
xdg-open ./my-architecture.html
```
## Design System & Visual Language
### Color Palette (Semantic Mapping)
Use specific `rgba` fills and hex strokes to categorize components:
<pathd="M 40 0 L 0 0 0 40"fill="none"stroke="#1e293b"stroke-width="0.5"/>
</pattern>
```
## Technical Implementation Details
### Component Rendering
Components are rounded rectangles (`rx="6"`) with 1.5px strokes. To prevent arrows from showing through semi-transparent fills, use a **double-rect masking technique**:
1. Draw an opaque background rect (`#0f172a`)
2. Draw the semi-transparent styled rect on top
### Connection Rules
- **Z-Order:** Draw arrows *early* in the SVG (after the grid) so they render behind component boxes
- **Arrowheads:** Defined via SVG markers
- **Security Flows:** Use dashed lines in rose color (`#fb7185`)
- **Boundaries:**
- *Security Groups:* Dashed (`4,4`), rose color
- *Regions:* Large dashed (`8,4`), amber color, `rx="12"`
- **Vertical Gap:** Minimum 40px between components
- **Message Buses:** Must be placed *in the gap* between services, not overlapping them
- **Legend Placement:** **CRITICAL.** Must be placed outside all boundary boxes. Calculate the lowest Y-coordinate of all boundaries and place the legend at least 20px below it.
## Document Structure
The generated HTML file follows a four-part layout:
1.**Header:** Title with a pulsing dot indicator and subtitle
2.**Main SVG:** The diagram contained within a rounded border card
3.**Summary Cards:** A grid of three cards below the diagram for high-level details
4.**Footer:** Minimal metadata
### Info Card Pattern
```html
<divclass="card">
<divclass="card-header">
<divclass="card-dot cyan"></div>
<h3>Title</h3>
</div>
<ul>
<li>• Item one</li>
<li>• Item two</li>
</ul>
</div>
```
## Output Requirements
- **Single File:** One self-contained `.html` file
- **No External Dependencies:** All CSS and SVG must be inline (except Google Fonts)
- **No JavaScript:** Use pure CSS for any animations (like pulsing dots)
- **Compatibility:** Must render correctly in any modern web browser
## Template Reference
Load the full HTML template for the exact structure, CSS, and SVG component examples:
The template contains working examples of every component type (frontend, backend, database, cloud, security), arrow styles (standard, dashed, curved), security groups, region boundaries, and the legend — use it as your structural reference when generating diagrams.