#577500

CSS

:root {
  --over-the-hills: #577500;
  --over-the-hills-rgb: 87 117 0;
  --over-the-hills-oklch: oklch(0.52 0.131 125.4);
}

.element {
  color: var(--over-the-hills);
  background-color: hsl(75 100% 23%);
  border-color: oklch(0.52 0.131 125.4);
}

Tailwind CSS v4

@theme {
  --color-over-the-hills: #577500;
  --color-over-the-hills-50: #ebfdd5;
  --color-over-the-hills-100: #dcf1c2;
  --color-over-the-hills-200: #c5dfa3;
  --color-over-the-hills-300: #a5c47a;
  --color-over-the-hills-400: #8cac50;
  --color-over-the-hills-500: #72941f;
  --color-over-the-hills-600: #607e1e;
  --color-over-the-hills-700: #4d6518;
  --color-over-the-hills-800: #3a490c;
  --color-over-the-hills-900: #273308;
  --color-over-the-hills-950: #161e00;
}

SCSS

$over-the-hills: #577500;
$over-the-hills-rgb: 87, 117, 0;
$over-the-hills-light: mix(#fff, $over-the-hills, 20%);
$over-the-hills-dark: mix(#000, $over-the-hills, 20%);

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