#392F2B

CSS

:root {
  --six-feet-under: #392f2b;
  --six-feet-under-rgb: 57 47 43;
  --six-feet-under-oklch: oklch(0.315 0.016 43);
}

.element {
  color: var(--six-feet-under);
  background-color: hsl(17 14% 20%);
  border-color: oklch(0.315 0.016 43);
}

Tailwind CSS v4

@theme {
  --color-six-feet-under: #392f2b;
  --color-six-feet-under-50: #f9f4f1;
  --color-six-feet-under-100: #ede6e3;
  --color-six-feet-under-200: #dbd2cf;
  --color-six-feet-under-300: #bfb5b1;
  --color-six-feet-under-400: #a79c97;
  --color-six-feet-under-500: #90837e;
  --color-six-feet-under-600: #7a6f6a;
  --color-six-feet-under-700: #625955;
  --color-six-feet-under-800: #48413e;
  --color-six-feet-under-900: #322d2b;
  --color-six-feet-under-950: #1e1a18;
}

SCSS

$six-feet-under: #392f2b;
$six-feet-under-rgb: 57, 47, 43;
$six-feet-under-light: mix(#fff, $six-feet-under, 20%);
$six-feet-under-dark: mix(#000, $six-feet-under, 20%);

.element {
  color: $six-feet-under;
  box-shadow: 0 0 0 2px rgba($six-feet-under, 0.35);
}