Intermediate
Compute a WCAG contrast ratio
Write contrast(a, b) so it returns the WCAG contrast ratio of two hex colours: relative luminance is 0.2126 R + 0.7152 G + 0.0722 B of the linear channels (v / 12.92 if v <= 0.04045, else ((v + 0.055) / 1.055) ** 2.4, with v from 0 to 1), and the ratio is (lighter + 0.05) / (darker + 0.05).
The page shows black on white (21.00) and #767676 on white (4.54). The starter always returns 1.
What Check tests
- Black on white is 21.00
- #767676 on white is 4.54
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