#0D191C

CSS

:root {
  --black-stallion: #0d191c;
  --black-stallion-rgb: 13 25 28;
  --black-stallion-oklch: oklch(0.204 0.018 215.2);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(192 37% 8%);
  border-color: oklch(0.204 0.018 215.2);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #0d191c;
  --color-black-stallion-50: #f0f6f8;
  --color-black-stallion-100: #e2e9ec;
  --color-black-stallion-200: #ccd6d9;
  --color-black-stallion-300: #aebabd;
  --color-black-stallion-400: #93a1a5;
  --color-black-stallion-500: #79898e;
  --color-black-stallion-600: #677478;
  --color-black-stallion-700: #525d60;
  --color-black-stallion-800: #3c4446;
  --color-black-stallion-900: #292f30;
  --color-black-stallion-950: #171c1d;
}

SCSS

$black-stallion: #0d191c;
$black-stallion-rgb: 13, 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);
}