#0A1922

CSS

:root {
  --black-stallion: #0a1922;
  --black-stallion-rgb: 10 25 34;
  --black-stallion-oklch: oklch(0.205 0.027 236.6);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(203 55% 9%);
  border-color: oklch(0.205 0.027 236.6);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #0a1922;
  --color-black-stallion-50: #eef6fc;
  --color-black-stallion-100: #e0e9f0;
  --color-black-stallion-200: #cad6df;
  --color-black-stallion-300: #abbac4;
  --color-black-stallion-400: #90a1ad;
  --color-black-stallion-500: #768996;
  --color-black-stallion-600: #64747f;
  --color-black-stallion-700: #505d66;
  --color-black-stallion-800: #39444b;
  --color-black-stallion-900: #272f34;
  --color-black-stallion-950: #151c1f;
}

SCSS

$black-stallion: #0a1922;
$black-stallion-rgb: 10, 25, 34;
$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);
}