#0F0710

CSS

:root {
  --noir-fiction: #0f0710;
  --noir-fiction-rgb: 15 7 16;
  --noir-fiction-oklch: oklch(0.146 0.024 323);
}

.element {
  color: var(--noir-fiction);
  background-color: hsl(293 39% 5%);
  border-color: oklch(0.146 0.024 323);
}

Tailwind CSS v4

@theme {
  --color-noir-fiction: #0f0710;
  --color-noir-fiction-50: #f9f3f9;
  --color-noir-fiction-100: #ece5ec;
  --color-noir-fiction-200: #dad1da;
  --color-noir-fiction-300: #beb3be;
  --color-noir-fiction-400: #a69aa7;
  --color-noir-fiction-500: #8e8190;
  --color-noir-fiction-600: #786d79;
  --color-noir-fiction-700: #605761;
  --color-noir-fiction-800: #464047;
  --color-noir-fiction-900: #312c32;
  --color-noir-fiction-950: #1d191d;
}

SCSS

$noir-fiction: #0f0710;
$noir-fiction-rgb: 15, 7, 16;
$noir-fiction-light: mix(#fff, $noir-fiction, 20%);
$noir-fiction-dark: mix(#000, $noir-fiction, 20%);

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