#637D3F

CSS

:root {
  --beyond-the-pines: #637d3f;
  --beyond-the-pines-rgb: 99 125 63;
  --beyond-the-pines-oklch: oklch(0.554 0.093 127.8);
}

.element {
  color: var(--beyond-the-pines);
  background-color: hsl(85 33% 37%);
  border-color: oklch(0.554 0.093 127.8);
}

Tailwind CSS v4

@theme {
  --color-beyond-the-pines: #637d3f;
  --color-beyond-the-pines-50: #ecfbdf;
  --color-beyond-the-pines-100: #deefce;
  --color-beyond-the-pines-200: #c7ddb3;
  --color-beyond-the-pines-300: #a8c18f;
  --color-beyond-the-pines-400: #8fa96d;
  --color-beyond-the-pines-500: #74924c;
  --color-beyond-the-pines-600: #637b41;
  --color-beyond-the-pines-700: #4f6334;
  --color-beyond-the-pines-800: #3a4823;
  --color-beyond-the-pines-900: #283217;
  --color-beyond-the-pines-950: #161e08;
}

SCSS

$beyond-the-pines: #637d3f;
$beyond-the-pines-rgb: 99, 125, 63;
$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);
}