blog-chart

Files (1)

• SKILL.md

SKILL.md (first lines)

# Blog Chart: Built-In SVG Data Visualization

Generates dark-mode-compatible inline SVG charts for blog posts. Invoked
internally by `blog-write` and `blog-rewrite` when chart-worthy data is
identified. Not a standalone user-facing command.

**Styling source of truth:** `references/visual-media.md`

## Input Format

The writer or researcher passes a chart request:

```
Chart Request:
- Type: horizontal bar
- Title: "AI Citation Sources by Platform"
- Data: ChatGPT 43.8%, Perplexity 6.6%, Google AI Overviews 2.2%, Reddit 7.15%
- Source: Ahrefs, December 2025
- Platform: mdx (or html)
```

## Chart Type Selection

Select based on the data pattern. Diversity is mandatory - never repeat a
type within one post.

| Data Pattern | Best Chart Type |
|-------------|-----------------|
| Before/after comparison | Grouped bar chart |
| Ranked factors / correlations | Lollipop chart |
| Parts of whole / market share | Donut chart |
| Trend over time | Line chart |
| Percentage improvement | Horizontal bar chart |
| Distribution / range | Area chart |
| Multi-dimensional scoring | Radar chart |

## Styling Rules (Non-Negotiable)

All charts must work on both dark and light backgrounds:

```
Text elements:     fill="currentColor"
Grid lines:        stroke="currentColor" opacity="0.08"
Axis lines:        stroke="currentColor" opacity="0.3"
Background:        transparent (no fill on root SVG)
Subtitle text:     fill="currentColor" opacity="0.45"
Source text:        fill="currentColor" opacity="0.35"
Label text:        fill="currentColor" opacity="0.8"
```

### Color Palette

| Color | Hex | Use Case |
|-------|-----|----------|
| Orange | `#f97316` | Primary / highest value |
| Sky Blue | `#38bdf8` | Secondary / comparison |
| Purple | `#a78bfa` | Tertiary / special category |
| Green | `#22c55e` | Quaternary / positive indicator |

For text inside colored elements: `fill="white"` with `fontWeight="800"`.

## Standard SVG Shell (HTML)

```xml
<svg
  viewBox="0 0 560 380"
  style="max-width: 100%; height: auto; font-family: 'Inter', system-ui, sans-serif"
  role="img"
  aria-label="Chart description with key data point"
>
  <title>Chart Title</title>
  <desc>Description for screen readers with all key data points and source</desc>

  <!-- Chart content -->

  <text x="280" y="372" text-anchor="middle" font-size="10" fill="currentColor" opacity="0.35">
    Source: Source Name (Year)
  </text>
</svg>
```

## JSX/MDX Shell (camelCase attributes)

```jsx
<svg
  viewBox="0 0 560 380"
  style={{maxWidth: '100%', height: 'auto', fontFamily: "'Inter', system-ui, sans-serif"}}
  role="img"
  aria-label="Chart description"
>
  <title>Chart Title</title>
  <desc>Description for screen readers</desc>

  {/* Chart content */}

  <text x="280" y="372" textAnchor="middle" fontSize="10" fill="currentColor" opacity="0.35">
    Source: Source Name (Year)
  </text>
</svg>
```

## JSX Attribute Conversion (Required for MDX)

| HTML | JSX |
|------|-----|
| `stroke-width` | `strokeWidth` |
| `stroke-dasharray` | `strokeDasharray` |
| `stroke-linecap` | `strokeLinecap` |
| `text-anchor` | `textAnchor` |
| `font-size` | `fontSize` |
| `font-weight` | `fontWeight` |
| `font-family` | `fontFamily` |
| `class` | `className` |
| `style="..."` | `style={{...}}` |

## Chart Type Construction

### Horizontal Bar Chart

From Infrasity-Labs/dev-gtm-claude-skills, MIT.

More from Infrasity-Labs/dev-gtm-claude-skills