#2B3D36

CSS

:root {
  --deep-forest: #2b3d36;
  --deep-forest-rgb: 43 61 54;
  --deep-forest-oklch: oklch(0.342 0.026 168.8);
}

.element {
  color: var(--deep-forest);
  background-color: hsl(157 17% 20%);
  border-color: oklch(0.342 0.026 168.8);
}

Tailwind CSS v4

@theme {
  --color-deep-forest: #2b3d36;
  --color-deep-forest-50: #eef8f4;
  --color-deep-forest-100: #e0ebe7;
  --color-deep-forest-200: #cad8d3;
  --color-deep-forest-300: #abbcb5;
  --color-deep-forest-400: #90a49c;
  --color-deep-forest-500: #768c83;
  --color-deep-forest-600: #64776f;
  --color-deep-forest-700: #505f59;
  --color-deep-forest-800: #3a4540;
  --color-deep-forest-900: #28302c;
  --color-deep-forest-950: #161c19;
}

SCSS

$deep-forest: #2b3d36;
$deep-forest-rgb: 43, 61, 54;
$deep-forest-light: mix(#fff, $deep-forest, 20%);
$deep-forest-dark: mix(#000, $deep-forest, 20%);

.element {
  color: $deep-forest;
  box-shadow: 0 0 0 2px rgba($deep-forest, 0.35);
}