#0D1A19

CSS

:root {
  --black-stallion: #0d1a19;
  --black-stallion-rgb: 13 26 25;
  --black-stallion-oklch: oklch(0.205 0.018 189.7);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(175 33% 8%);
  border-color: oklch(0.205 0.018 189.7);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #0d1a19;
  --color-black-stallion-50: #eff7f6;
  --color-black-stallion-100: #e1eae9;
  --color-black-stallion-200: #ccd7d6;
  --color-black-stallion-300: #adbbba;
  --color-black-stallion-400: #93a2a1;
  --color-black-stallion-500: #798a89;
  --color-black-stallion-600: #667574;
  --color-black-stallion-700: #525e5c;
  --color-black-stallion-800: #3b4543;
  --color-black-stallion-900: #292f2f;
  --color-black-stallion-950: #171c1b;
}

SCSS

$black-stallion: #0d1a19;
$black-stallion-rgb: 13, 26, 25;
$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);
}