#59716E

CSS

:root {
  --dark-forest: #59716e;
  --dark-forest-rgb: 89 113 110;
  --dark-forest-oklch: oklch(0.528 0.029 187);
}

.element {
  color: var(--dark-forest);
  background-color: hsl(173 12% 40%);
  border-color: oklch(0.528 0.029 187);
}

Tailwind CSS v4

@theme {
  --color-dark-forest: #59716e;
  --color-dark-forest-50: #ecf8f7;
  --color-dark-forest-100: #deebea;
  --color-dark-forest-200: #c7d8d7;
  --color-dark-forest-300: #a8bcba;
  --color-dark-forest-400: #8ca4a1;
  --color-dark-forest-500: #718d89;
  --color-dark-forest-600: #607774;
  --color-dark-forest-700: #4d5f5d;
  --color-dark-forest-800: #384644;
  --color-dark-forest-900: #26302f;
  --color-dark-forest-950: #141c1b;
}

SCSS

$dark-forest: #59716e;
$dark-forest-rgb: 89, 113, 110;
$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);
}