#0B3211

CSS

:root {
  --dark-serpent: #0b3211;
  --dark-serpent-rgb: 11 50 17;
  --dark-serpent-oklch: oklch(0.281 0.072 146);
}

.element {
  color: var(--dark-serpent);
  background-color: hsl(129 64% 12%);
  border-color: oklch(0.281 0.072 146);
}

Tailwind CSS v4

@theme {
  --color-dark-serpent: #0b3211;
  --color-dark-serpent-50: #e8fbea;
  --color-dark-serpent-100: #d9efdb;
  --color-dark-serpent-200: #c0ddc3;
  --color-dark-serpent-300: #9fc2a3;
  --color-dark-serpent-400: #83aa85;
  --color-dark-serpent-500: #679369;
  --color-dark-serpent-600: #577d59;
  --color-dark-serpent-700: #466447;
  --color-dark-serpent-800: #334932;
  --color-dark-serpent-900: #233322;
  --color-dark-serpent-950: #121e11;
}

SCSS

$dark-serpent: #0b3211;
$dark-serpent-rgb: 11, 50, 17;
$dark-serpent-light: mix(#fff, $dark-serpent, 20%);
$dark-serpent-dark: mix(#000, $dark-serpent, 20%);

.element {
  color: $dark-serpent;
  box-shadow: 0 0 0 2px rgba($dark-serpent, 0.35);
}