#031113

CSS

:root {
  --black-stallion: #031113;
  --black-stallion-rgb: 3 17 19;
  --black-stallion-oklch: oklch(0.165 0.022 206.2);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(188 73% 4%);
  border-color: oklch(0.165 0.022 206.2);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #031113;
  --color-black-stallion-50: #eef7f8;
  --color-black-stallion-100: #e0eaec;
  --color-black-stallion-200: #cad7d9;
  --color-black-stallion-300: #abbbbd;
  --color-black-stallion-400: #90a2a5;
  --color-black-stallion-500: #768b8d;
  --color-black-stallion-600: #647578;
  --color-black-stallion-700: #505e60;
  --color-black-stallion-800: #3a4546;
  --color-black-stallion-900: #283030;
  --color-black-stallion-950: #161c1d;
}

SCSS

$black-stallion: #031113;
$black-stallion-rgb: 3, 17, 19;
$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);
}