#0F1920

CSS

:root {
  --black-stallion: #0f1920;
  --black-stallion-rgb: 15 25 32;
  --black-stallion-oklch: oklch(0.207 0.02 239.5);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(205 36% 9%);
  border-color: oklch(0.207 0.02 239.5);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #0f1920;
  --color-black-stallion-50: #f0f6fa;
  --color-black-stallion-100: #e2e9ee;
  --color-black-stallion-200: #cdd5dc;
  --color-black-stallion-300: #afb9c1;
  --color-black-stallion-400: #94a0a9;
  --color-black-stallion-500: #7b8892;
  --color-black-stallion-600: #68737c;
  --color-black-stallion-700: #535c63;
  --color-black-stallion-800: #3c4449;
  --color-black-stallion-900: #292f32;
  --color-black-stallion-950: #171b1e;
}

SCSS

$black-stallion: #0f1920;
$black-stallion-rgb: 15, 25, 32;
$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);
}