#303900

CSS

:root {
  --dark-olive: #303900;
  --dark-olive-rgb: 48 57 0;
  --dark-olive-oklch: oklch(0.325 0.076 119.1);
}

.element {
  color: var(--dark-olive);
  background-color: hsl(69 100% 11%);
  border-color: oklch(0.325 0.076 119.1);
}

Tailwind CSS v4

@theme {
  --color-dark-olive: #303900;
  --color-dark-olive-50: #f1f9e1;
  --color-dark-olive-100: #e4ecd0;
  --color-dark-olive-200: #cfdab6;
  --color-dark-olive-300: #b1be92;
  --color-dark-olive-400: #99a572;
  --color-dark-olive-500: #808e52;
  --color-dark-olive-600: #6d7846;
  --color-dark-olive-700: #576038;
  --color-dark-olive-800: #404627;
  --color-dark-olive-900: #2c301a;
  --color-dark-olive-950: #191d0a;
}

SCSS

$dark-olive: #303900;
$dark-olive-rgb: 48, 57, 0;
$dark-olive-light: mix(#fff, $dark-olive, 20%);
$dark-olive-dark: mix(#000, $dark-olive, 20%);

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