#56726A

CSS

:root {
  --dark-forest: #56726a;
  --dark-forest-rgb: 86 114 106;
  --dark-forest-oklch: oklch(0.528 0.035 175.5);
}

.element {
  color: var(--dark-forest);
  background-color: hsl(163 14% 39%);
  border-color: oklch(0.528 0.035 175.5);
}

Tailwind CSS v4

@theme {
  --color-dark-forest: #56726a;
  --color-dark-forest-50: #ebf9f5;
  --color-dark-forest-100: #dcece8;
  --color-dark-forest-200: #c5d9d4;
  --color-dark-forest-300: #a5beb7;
  --color-dark-forest-400: #8aa69d;
  --color-dark-forest-500: #6e8e85;
  --color-dark-forest-600: #5e7871;
  --color-dark-forest-700: #4b605a;
  --color-dark-forest-800: #364641;
  --color-dark-forest-900: #25312d;
  --color-dark-forest-950: #131d1a;
}

SCSS

$dark-forest: #56726a;
$dark-forest-rgb: 86, 114, 106;
$dark-forest-light: mix(#fff, $dark-forest, 20%);
$dark-forest-dark: mix(#000, $dark-forest, 20%);

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