#7F791D

CSS

:root {
  --olive: #7f791d;
  --olive-rgb: 127 121 29;
  --olive-oklch: oklch(0.564 0.109 105.6);
}

.element {
  color: var(--olive);
  background-color: hsl(56 63% 31%);
  border-color: oklch(0.564 0.109 105.6);
}

Tailwind CSS v4

@theme {
  --color-olive: #7f791d;
  --color-olive-50: #f8f8d4;
  --color-olive-100: #ebebc2;
  --color-olive-200: #d9d8a2;
  --color-olive-300: #bdbc79;
  --color-olive-400: #a7a251;
  --color-olive-500: #918a22;
  --color-olive-600: #7a7520;
  --color-olive-700: #625d19;
  --color-olive-800: #49440f;
  --color-olive-900: #332f09;
  --color-olive-950: #1e1b00;
}

SCSS

$olive: #7f791d;
$olive-rgb: 127, 121, 29;
$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);
}