#636F6C

CSS

:root {
  --wrapped-in-twilight: #636f6c;
  --wrapped-in-twilight-rgb: 99 111 108;
  --wrapped-in-twilight-oklch: oklch(0.531 0.015 179);
}

.element {
  color: var(--wrapped-in-twilight);
  background-color: hsl(165 6% 41%);
  border-color: oklch(0.531 0.015 179);
}

Tailwind CSS v4

@theme {
  --color-wrapped-in-twilight: #636f6c;
  --color-wrapped-in-twilight-50: #f1f7f5;
  --color-wrapped-in-twilight-100: #e3eae8;
  --color-wrapped-in-twilight-200: #ced6d4;
  --color-wrapped-in-twilight-300: #afbab8;
  --color-wrapped-in-twilight-400: #95a19e;
  --color-wrapped-in-twilight-500: #7c8a86;
  --color-wrapped-in-twilight-600: #697472;
  --color-wrapped-in-twilight-700: #545d5b;
  --color-wrapped-in-twilight-800: #3d4442;
  --color-wrapped-in-twilight-900: #2a2f2e;
  --color-wrapped-in-twilight-950: #181c1a;
}

SCSS

$wrapped-in-twilight: #636f6c;
$wrapped-in-twilight-rgb: 99, 111, 108;
$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);
}