#0D2F1A

CSS

:root {
  --pitch-black-forests: #0d2f1a;
  --pitch-black-forests-rgb: 13 47 26;
  --pitch-black-forests-oklch: oklch(0.274 0.055 153.4);
}

.element {
  color: var(--pitch-black-forests);
  background-color: hsl(143 57% 12%);
  border-color: oklch(0.274 0.055 153.4);
}

Tailwind CSS v4

@theme {
  --color-pitch-black-forests: #0d2f1a;
  --color-pitch-black-forests-50: #e9faee;
  --color-pitch-black-forests-100: #daeee0;
  --color-pitch-black-forests-200: #c2dcca;
  --color-pitch-black-forests-300: #a2c0ab;
  --color-pitch-black-forests-400: #86a88f;
  --color-pitch-black-forests-500: #6a9175;
  --color-pitch-black-forests-600: #5a7b63;
  --color-pitch-black-forests-700: #48624f;
  --color-pitch-black-forests-800: #344839;
  --color-pitch-black-forests-900: #243227;
  --color-pitch-black-forests-950: #121e15;
}

SCSS

$pitch-black-forests: #0d2f1a;
$pitch-black-forests-rgb: 13, 47, 26;
$pitch-black-forests-light: mix(#fff, $pitch-black-forests, 20%);
$pitch-black-forests-dark: mix(#000, $pitch-black-forests, 20%);

.element {
  color: $pitch-black-forests;
  box-shadow: 0 0 0 2px rgba($pitch-black-forests, 0.35);
}