#0F0310

CSS

:root {
  --noir-fiction: #0f0310;
  --noir-fiction-rgb: 15 3 16;
  --noir-fiction-oklch: oklch(0.132 0.039 325);
}

.element {
  color: var(--noir-fiction);
  background-color: hsl(295 68% 4%);
  border-color: oklch(0.132 0.039 325);
}

Tailwind CSS v4

@theme {
  --color-noir-fiction: #0f0310;
  --color-noir-fiction-50: #fcf1fb;
  --color-noir-fiction-100: #efe4ef;
  --color-noir-fiction-200: #decfdd;
  --color-noir-fiction-300: #c3b1c2;
  --color-noir-fiction-400: #ab97ab;
  --color-noir-fiction-500: #947e95;
  --color-noir-fiction-600: #7d6a7e;
  --color-noir-fiction-700: #645565;
  --color-noir-fiction-800: #493e4a;
  --color-noir-fiction-900: #332b34;
  --color-noir-fiction-950: #1e181f;
}

SCSS

$noir-fiction: #0f0310;
$noir-fiction-rgb: 15, 3, 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);
}