#001717

CSS

:root {
  --black-stallion: #001717;
  --black-stallion-rgb: 0 23 23;
  --black-stallion-oklch: oklch(0.185 0.032 194.8);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(180 100% 5%);
  border-color: oklch(0.185 0.032 194.8);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #001717;
  --color-black-stallion-50: #ebf8f8;
  --color-black-stallion-100: #dcebeb;
  --color-black-stallion-200: #c6d9d9;
  --color-black-stallion-300: #a6bdbd;
  --color-black-stallion-400: #8aa5a4;
  --color-black-stallion-500: #6e8d8c;
  --color-black-stallion-600: #5e7777;
  --color-black-stallion-700: #4b605f;
  --color-black-stallion-800: #364645;
  --color-black-stallion-900: #253030;
  --color-black-stallion-950: #131d1c;
}

SCSS

$black-stallion: #001717;
$black-stallion-rgb: 0, 23, 23;
$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);
}