#12191C

CSS

:root {
  --black-stallion: #12191c;
  --black-stallion-rgb: 18 25 28;
  --black-stallion-oklch: oklch(0.208 0.012 225.8);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(198 22% 9%);
  border-color: oklch(0.208 0.012 225.8);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #12191c;
  --color-black-stallion-50: #f2f6f8;
  --color-black-stallion-100: #e4e9eb;
  --color-black-stallion-200: #cfd5d8;
  --color-black-stallion-300: #b1b9bc;
  --color-black-stallion-400: #97a0a4;
  --color-black-stallion-500: #7e888c;
  --color-black-stallion-600: #6b7377;
  --color-black-stallion-700: #555c5f;
  --color-black-stallion-800: #3e4345;
  --color-black-stallion-900: #2b2e30;
  --color-black-stallion-950: #181b1c;
}

SCSS

$black-stallion: #12191c;
$black-stallion-rgb: 18, 25, 28;
$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);
}