#00131A

CSS

:root {
  --black-stallion: #00131a;
  --black-stallion-rgb: 0 19 26;
  --black-stallion-oklch: oklch(0.173 0.032 221.9);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(196 100% 5%);
  border-color: oklch(0.173 0.032 221.9);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #00131a;
  --color-black-stallion-50: #ecf7fc;
  --color-black-stallion-100: #ddeaf0;
  --color-black-stallion-200: #c6d8de;
  --color-black-stallion-300: #a7bbc4;
  --color-black-stallion-400: #8ba3ac;
  --color-black-stallion-500: #6f8b95;
  --color-black-stallion-600: #5f767e;
  --color-black-stallion-700: #4b5e65;
  --color-black-stallion-800: #36454a;
  --color-black-stallion-900: #253033;
  --color-black-stallion-950: #141c1f;
}

SCSS

$black-stallion: #00131a;
$black-stallion-rgb: 0, 19, 26;
$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);
}