#777919

CSS

:root {
  --olive: #777919;
  --olive-rgb: 119 121 25;
  --olive-oklch: oklch(0.557 0.113 110.8);
}

.element {
  color: var(--olive);
  background-color: hsl(61 66% 29%);
  border-color: oklch(0.557 0.113 110.8);
}

Tailwind CSS v4

@theme {
  --color-olive: #777919;
  --color-olive-50: #f5f9d5;
  --color-olive-100: #e8edc2;
  --color-olive-200: #d4daa2;
  --color-olive-300: #b8be79;
  --color-olive-400: #a1a551;
  --color-olive-500: #8a8c21;
  --color-olive-600: #75771f;
  --color-olive-700: #5d5f19;
  --color-olive-800: #46450e;
  --color-olive-900: #303009;
  --color-olive-950: #1d1c00;
}

SCSS

$olive: #777919;
$olive-rgb: 119, 121, 25;
$olive-light: mix(#fff, $olive, 20%);
$olive-dark: mix(#000, $olive, 20%);

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