#6C3132

CSS

:root {
  --arcane-red: #6c3132;
  --arcane-red-rgb: 108 49 50;
  --arcane-red-oklch: oklch(0.393 0.084 20.7);
}

.element {
  color: var(--arcane-red);
  background-color: hsl(359 38% 31%);
  border-color: oklch(0.393 0.084 20.7);
}

Tailwind CSS v4

@theme {
  --color-arcane-red: #6c3132;
  --color-arcane-red-50: #ffecea;
  --color-arcane-red-100: #ffdedb;
  --color-arcane-red-200: #f7c7c4;
  --color-arcane-red-300: #e0a7a4;
  --color-arcane-red-400: #cc8b89;
  --color-arcane-red-500: #b86f6e;
  --color-arcane-red-600: #9b5e5d;
  --color-arcane-red-700: #7c4b4a;
  --color-arcane-red-800: #5c3637;
  --color-arcane-red-900: #412525;
  --color-arcane-red-950: #291314;
}

SCSS

$arcane-red: #6c3132;
$arcane-red-rgb: 108, 49, 50;
$arcane-red-light: mix(#fff, $arcane-red, 20%);
$arcane-red-dark: mix(#000, $arcane-red, 20%);

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