#140A0F

CSS

:root {
  --noir-fiction: #140a0f;
  --noir-fiction-rgb: 20 10 15;
  --noir-fiction-oklch: oklch(0.161 0.02 348.2);
}

.element {
  color: var(--noir-fiction);
  background-color: hsl(330 33% 6%);
  border-color: oklch(0.161 0.02 348.2);
}

Tailwind CSS v4

@theme {
  --color-noir-fiction: #140a0f;
  --color-noir-fiction-50: #faf3f6;
  --color-noir-fiction-100: #ede5e9;
  --color-noir-fiction-200: #dbd1d5;
  --color-noir-fiction-300: #c0b3b9;
  --color-noir-fiction-400: #a89aa0;
  --color-noir-fiction-500: #918188;
  --color-noir-fiction-600: #7b6d73;
  --color-noir-fiction-700: #62575c;
  --color-noir-fiction-800: #484044;
  --color-noir-fiction-900: #322c2f;
  --color-noir-fiction-950: #1e191b;
}

SCSS

$noir-fiction: #140a0f;
$noir-fiction-rgb: 20, 10, 15;
$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);
}