#121918

CSS

:root {
  --black-stallion: #121918;
  --black-stallion-rgb: 18 25 24;
  --black-stallion-oklch: oklch(0.206 0.011 185.7);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(171 16% 8%);
  border-color: oklch(0.206 0.011 185.7);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #121918;
  --color-black-stallion-50: #f2f6f6;
  --color-black-stallion-100: #e4e9e8;
  --color-black-stallion-200: #cfd6d5;
  --color-black-stallion-300: #b2b9b8;
  --color-black-stallion-400: #98a19f;
  --color-black-stallion-500: #7f8987;
  --color-black-stallion-600: #6b7472;
  --color-black-stallion-700: #565c5b;
  --color-black-stallion-800: #3f4443;
  --color-black-stallion-900: #2b2f2e;
  --color-black-stallion-950: #181b1b;
}

SCSS

$black-stallion: #121918;
$black-stallion-rgb: 18, 25, 24;
$black-stallion-light: mix(#fff, $black-stallion, 20%);
$black-stallion-dark: mix(#000, $black-stallion, 20%);

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