#001417

CSS

:root {
  --black-stallion: #001417;
  --black-stallion-rgb: 0 20 23;
  --black-stallion-oklch: oklch(0.175 0.03 206.8);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(188 100% 5%);
  border-color: oklch(0.175 0.03 206.8);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #001417;
  --color-black-stallion-50: #ecf8fa;
  --color-black-stallion-100: #ddebed;
  --color-black-stallion-200: #c6d8db;
  --color-black-stallion-300: #a7bcc0;
  --color-black-stallion-400: #8ba4a7;
  --color-black-stallion-500: #708c90;
  --color-black-stallion-600: #5f777a;
  --color-black-stallion-700: #4b5f62;
  --color-black-stallion-800: #374647;
  --color-black-stallion-900: #253031;
  --color-black-stallion-950: #141c1d;
}

SCSS

$black-stallion: #001417;
$black-stallion-rgb: 0, 20, 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);
}