About gray-400
#99A1AF is gray-400, a tailwind v4. This page shows its rgb(153, 161, 175) / hsl(218.18, 12.09%, 64.31%) / oklch(0.7071 0.0224 261.75) values, WCAG contrast against black and white, an OKLCH tint-and-shade ramp, and complementary, analogous, and triadic harmonies — all computed in perceptually-uniform OKLCH.