#004900

CSS

:root {
  --woodland-grass: #004900;
  --woodland-grass-rgb: 0 73 0;
  --woodland-grass-oklch: oklch(0.351 0.12 142.5);
}

.element {
  color: var(--woodland-grass);
  background-color: hsl(120 100% 14%);
  border-color: oklch(0.351 0.12 142.5);
}

Tailwind CSS v4

@theme {
  --color-woodland-grass: #004900;
  --color-woodland-grass-50: #e1ffe0;
  --color-woodland-grass-100: #d0f3d0;
  --color-woodland-grass-200: #b5e2b5;
  --color-woodland-grass-300: #91c891;
  --color-woodland-grass-400: #73b06e;
  --color-woodland-grass-500: #529a4d;
  --color-woodland-grass-600: #478242;
  --color-woodland-grass-700: #386835;
  --color-woodland-grass-800: #2a4c23;
  --color-woodland-grass-900: #1c3517;
  --color-woodland-grass-950: #0c2008;
}

SCSS

$woodland-grass: #004900;
$woodland-grass-rgb: 0, 73, 0;
$woodland-grass-light: mix(#fff, $woodland-grass, 20%);
$woodland-grass-dark: mix(#000, $woodland-grass, 20%);

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