{
  "title": "When color cannot carry the message",
  "prepared": "2026-09-27",
  "kind": "Original teaching examples informed by W3C guidance; not participant or gameplay data",
  "sources": [
    {"id":"color","title":"W3C: Understanding 1.4.1 Use of Color","url":"https://www.w3.org/WAI/WCAG22/Understanding/use-of-color.html"},
    {"id":"patterns","title":"W3C technique G111: Using color and pattern","url":"https://www.w3.org/WAI/WCAG22/Techniques/general/G111"},
    {"id":"text","title":"W3C: Understanding 1.4.3 Contrast (Minimum)","url":"https://www.w3.org/WAI/WCAG22/Understanding/contrast-minimum.html"},
    {"id":"graphics","title":"W3C: Understanding 1.4.11 Non-text Contrast","url":"https://www.w3.org/WAI/WCAG22/Understanding/non-text-contrast.html"},
    {"id":"images","title":"W3C WAI: Complex Images tutorial","url":"https://www.w3.org/WAI/tutorials/images/complex/"},
    {"id":"formula","title":"WCAG 2.2: Relative luminance definition","url":"https://www.w3.org/TR/WCAG22/#dfn-relative-luminance"}
  ],
  "statusExample": [
    {"parcel":"01","label":"Delivered","shape":"circle","symbol":"✓","color":"#08756b"},
    {"parcel":"02","label":"Delayed","shape":"diamond","symbol":"!","color":"#a55a00"},
    {"parcel":"03","label":"Action needed","shape":"square","symbol":"!","color":"#b23b57"}
  ],
  "singleInk": {"color":"#475569","method":"Replace all three status colors with exactly the same ink. This also removes lightness differences. It is not grayscale conversion, a color-vision simulation, or an accessibility conformance test."},
  "chart": {
    "title":"Completed tasks in an invented four-day example",
    "days":["Day 1","Day 2","Day 3","Day 4"],
    "series":[
      {"name":"Series A","values":[2,5,4,8],"color":"#2855cf","line":"solid","marker":"circle"},
      {"name":"Series B","values":[1,3,6,5],"color":"#b8412d","line":"dashed","marker":"diamond"}
    ],
    "scale":{"min":0,"max":10,"unit":"completed tasks"}
  },
  "contrastExamples":[
    {"name":"Faint ink","foreground":"#a9b8d4","background":"#ffffff","purpose":"Intentionally insufficient contrast; demonstration only"},
    {"name":"Stronger ink","foreground":"#2855cf","background":"#ffffff","purpose":"Comparison with sufficient normal-text contrast"}
  ],
  "contrastMethod":"Convert each 8-bit sRGB channel to 0–1. If channel <= 0.04045, divide by 12.92; otherwise ((channel+0.055)/1.055)^2.4. L=0.2126R+0.7152G+0.0722B. Contrast=(lighter L+0.05)/(darker L+0.05). Display two decimals; compare unrounded ratios with thresholds.",
  "limits":["Examples do not certify a product or palette as accessible.","No vision condition is simulated or diagnosed.","The diagram artwork is original; it is not an audit or redesign of the playable games.","Chart values are invented solely to demonstrate visual encoding."]
}