#637F39

CSS

:root {
  --beyond-the-pines: #637f39;
  --beyond-the-pines-rgb: 99 127 57;
  --beyond-the-pines-oklch: oklch(0.558 0.103 127.5);
}

.element {
  color: var(--beyond-the-pines);
  background-color: hsl(84 38% 36%);
  border-color: oklch(0.558 0.103 127.5);
}

Tailwind CSS v4

@theme {
  --color-beyond-the-pines: #637f39;
  --color-beyond-the-pines-50: #ecfcdd;
  --color-beyond-the-pines-100: #ddefcb;
  --color-beyond-the-pines-200: #c6deaf;
  --color-beyond-the-pines-300: #a7c28a;
  --color-beyond-the-pines-400: #8daa67;
  --color-beyond-the-pines-500: #739344;
  --color-beyond-the-pines-600: #627c3a;
  --color-beyond-the-pines-700: #4e632e;
  --color-beyond-the-pines-800: #3a491f;
  --color-beyond-the-pines-900: #283214;
  --color-beyond-the-pines-950: #161e06;
}

SCSS

$beyond-the-pines: #637f39;
$beyond-the-pines-rgb: 99, 127, 57;
$beyond-the-pines-light: mix(#fff, $beyond-the-pines, 20%);
$beyond-the-pines-dark: mix(#000, $beyond-the-pines, 20%);

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