#7F761F

CSS

:root {
  --olive: #7f761f;
  --olive-rgb: 127 118 31;
  --olive-oklch: oklch(0.558 0.105 103.3);
}

.element {
  color: var(--olive);
  background-color: hsl(54 61% 31%);
  border-color: oklch(0.558 0.105 103.3);
}

Tailwind CSS v4

@theme {
  --color-olive: #7f761f;
  --color-olive-50: #f9f8d5;
  --color-olive-100: #ecebc3;
  --color-olive-200: #dad7a4;
  --color-olive-300: #bfbb7b;
  --color-olive-400: #a9a154;
  --color-olive-500: #938927;
  --color-olive-600: #7c7424;
  --color-olive-700: #635d1c;
  --color-olive-800: #4a4311;
  --color-olive-900: #332e0b;
  --color-olive-950: #1f1b01;
}

SCSS

$olive: #7f761f;
$olive-rgb: 127, 118, 31;
$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);
}