#120207

CSS

:root {
  --dark-matter: #120207;
  --dark-matter-rgb: 18 2 7;
  --dark-matter-oklch: oklch(0.128 0.038 357.6);
}

.element {
  color: var(--dark-matter);
  background-color: hsl(341 80% 4%);
  border-color: oklch(0.128 0.038 357.6);
}

Tailwind CSS v4

@theme {
  --color-dark-matter: #120207;
  --color-dark-matter-50: #fff1f5;
  --color-dark-matter-100: #f4e3e7;
  --color-dark-matter-200: #e3ced3;
  --color-dark-matter-300: #c9b0b7;
  --color-dark-matter-400: #b2959e;
  --color-dark-matter-500: #9c7c86;
  --color-dark-matter-600: #846971;
  --color-dark-matter-700: #6a545b;
  --color-dark-matter-800: #4e3d43;
  --color-dark-matter-900: #362a2e;
  --color-dark-matter-950: #21181b;
}

SCSS

$dark-matter: #120207;
$dark-matter-rgb: 18, 2, 7;
$dark-matter-light: mix(#fff, $dark-matter, 20%);
$dark-matter-dark: mix(#000, $dark-matter, 20%);

.element {
  color: $dark-matter;
  box-shadow: 0 0 0 2px rgba($dark-matter, 0.35);
}