#7D791F

CSS

:root {
  --olive: #7d791f;
  --olive-rgb: 125 121 31;
  --olive-oklch: oklch(0.563 0.108 106.8);
}

.element {
  color: var(--olive);
  background-color: hsl(57 60% 31%);
  border-color: oklch(0.563 0.108 106.8);
}

Tailwind CSS v4

@theme {
  --color-olive: #7d791f;
  --color-olive-50: #f7f8d5;
  --color-olive-100: #eaebc2;
  --color-olive-200: #d7d9a3;
  --color-olive-300: #bbbc7b;
  --color-olive-400: #a6a353;
  --color-olive-500: #8f8a25;
  --color-olive-600: #797522;
  --color-olive-700: #615e1b;
  --color-olive-800: #484410;
  --color-olive-900: #322f0a;
  --color-olive-950: #1e1b00;
}

SCSS

$olive: #7d791f;
$olive-rgb: 125, 121, 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);
}