#636E6F

CSS

:root {
  --wrapped-in-twilight: #636e6f;
  --wrapped-in-twilight-rgb: 99 110 111;
  --wrapped-in-twilight-oklch: oklch(0.529 0.013 203.4);
}

.element {
  color: var(--wrapped-in-twilight);
  background-color: hsl(185 6% 41%);
  border-color: oklch(0.529 0.013 203.4);
}

Tailwind CSS v4

@theme {
  --color-wrapped-in-twilight: #636e6f;
  --color-wrapped-in-twilight-50: #f1f6f7;
  --color-wrapped-in-twilight-100: #e3e9ea;
  --color-wrapped-in-twilight-200: #ced6d7;
  --color-wrapped-in-twilight-300: #b0b9bb;
  --color-wrapped-in-twilight-400: #96a1a2;
  --color-wrapped-in-twilight-500: #7c898a;
  --color-wrapped-in-twilight-600: #697475;
  --color-wrapped-in-twilight-700: #545d5d;
  --color-wrapped-in-twilight-800: #3d4444;
  --color-wrapped-in-twilight-900: #2a2f2f;
  --color-wrapped-in-twilight-950: #181b1c;
}

SCSS

$wrapped-in-twilight: #636e6f;
$wrapped-in-twilight-rgb: 99, 110, 111;
$wrapped-in-twilight-light: mix(#fff, $wrapped-in-twilight, 20%);
$wrapped-in-twilight-dark: mix(#000, $wrapped-in-twilight, 20%);

.element {
  color: $wrapped-in-twilight;
  box-shadow: 0 0 0 2px rgba($wrapped-in-twilight, 0.35);
}