#90A346

CSS

:root {
  --lime-it-or-leave-it: #90a346;
  --lime-it-or-leave-it-rgb: 144 163 70;
  --lime-it-or-leave-it-oklch: oklch(0.681 0.121 119.4);
}

.element {
  color: var(--lime-it-or-leave-it);
  background-color: hsl(72 40% 46%);
  border-color: oklch(0.681 0.121 119.4);
}

Tailwind CSS v4

@theme {
  --color-lime-it-or-leave-it: #90a346;
  --color-lime-it-or-leave-it-50: #effbd5;
  --color-lime-it-or-leave-it-100: #e1efc2;
  --color-lime-it-or-leave-it-200: #ccdda3;
  --color-lime-it-or-leave-it-300: #aec17a;
  --color-lime-it-or-leave-it-400: #96a952;
  --color-lime-it-or-leave-it-500: #7d9122;
  --color-lime-it-or-leave-it-600: #6a7b20;
  --color-lime-it-or-leave-it-700: #556219;
  --color-lime-it-or-leave-it-800: #3f470e;
  --color-lime-it-or-leave-it-900: #2c3209;
  --color-lime-it-or-leave-it-950: #191d00;
}

SCSS

$lime-it-or-leave-it: #90a346;
$lime-it-or-leave-it-rgb: 144, 163, 70;
$lime-it-or-leave-it-light: mix(#fff, $lime-it-or-leave-it, 20%);
$lime-it-or-leave-it-dark: mix(#000, $lime-it-or-leave-it, 20%);

.element {
  color: $lime-it-or-leave-it;
  box-shadow: 0 0 0 2px rgba($lime-it-or-leave-it, 0.35);
}