Hot Pink Passes WCAG. That's the Problem.
WCAG's contrast formula was built for 1999 display calibration, not legibility. Hot pink on near-black scores 6.6:1 and passes — and isn't readable. OKCA closes the gap at the algorithm layer with chroma compression, polarity-aware scaling, and a zero-false-pass invariant — proven on the grey axis and verified across 1,249 production pairs and the sRGB gamut.