skills

{
 "_note": "The 600x290 preview in assets/preview.svg: the stack chart of themes.data.json, with no title or footnote. Rebuild: draw_stack.py --spec examples/readme-sections/preview.spec.json --out preview.html --svg assets/preview.svg",
 "data": "themes.data.json",
 "aria": "Headings per README by theme, 2014 to 2025: API reference entries grew, usage and how-to sections shrank",
 "count_label": "READMEs",
 "y_step": 4,
 "arrow": ["{change_pct:+.0f}%: {total_from:.1f} → {total_to:.1f}"],
 "layout": {"width": 600, "height": 290, "x0": 72, "x1": 346, "y_bottom": 236, "plot_height": 190},
 "period_labels": ["2014", "2016", "2018", "2020", "2022", "’24", "’25"]
}