#0D1920

CSS

:root {
  --black-stallion: #0d1920;
  --black-stallion-rgb: 13 25 32;
  --black-stallion-oklch: oklch(0.206 0.022 234.9);
}

.element {
  color: var(--black-stallion);
  background-color: hsl(202 42% 9%);
  border-color: oklch(0.206 0.022 234.9);
}

Tailwind CSS v4

@theme {
  --color-black-stallion: #0d1920;
  --color-black-stallion-50: #eff6fb;
  --color-black-stallion-100: #e1e9ee;
  --color-black-stallion-200: #ccd6dd;
  --color-black-stallion-300: #adb9c1;
  --color-black-stallion-400: #92a1aa;
  --color-black-stallion-500: #798993;
  --color-black-stallion-600: #66747c;
  --color-black-stallion-700: #525d63;
  --color-black-stallion-800: #3b4449;
  --color-black-stallion-900: #292f33;
  --color-black-stallion-950: #161b1e;
}

SCSS

$black-stallion: #0d1920;
$black-stallion-rgb: 13, 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);
}