#060603

CSS

:root {
  --black-metal: #060603;
  --black-metal-rgb: 6 6 3;
  --black-metal-oklch: oklch(0.12 0.01 107.9);
}

.element {
  color: var(--black-metal);
  background-color: hsl(60 33% 2%);
  border-color: oklch(0.12 0.01 107.9);
}

Tailwind CSS v4

@theme {
  --color-black-metal: #060603;
  --color-black-metal-50: #f5f5f2;
  --color-black-metal-100: #e8e8e4;
  --color-black-metal-200: #d4d5d0;
  --color-black-metal-300: #b7b8b2;
  --color-black-metal-400: #9f9f98;
  --color-black-metal-500: #87877f;
  --color-black-metal-600: #72726c;
  --color-black-metal-700: #5b5b56;
  --color-black-metal-800: #43433f;
  --color-black-metal-900: #2e2e2b;
  --color-black-metal-950: #1b1b18;
}

SCSS

$black-metal: #060603;
$black-metal-rgb: 6, 6, 3;
$black-metal-light: mix(#fff, $black-metal, 20%);
$black-metal-dark: mix(#000, $black-metal, 20%);

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