isLightText vs W3C luminance
Pick a background — compare both algorithms side‑by‑side
isLightText boundary
W3C luminance boundary
isLightText
Sample Text
Returns true → use
white text
W3C luminance
Sample Text
Returns true → use
white text
#2c3e50 · rgb(44, 62, 80)
luminance = 0.000 · sigmoid = 0.000
algorithms agree