#040905

CSS

:root {
  --black-metal: #040905;
  --black-metal-rgb: 4 9 5;
  --black-metal-oklch: oklch(0.131 0.015 151.4);
}

.element {
  color: var(--black-metal);
  background-color: hsl(132 38% 3%);
  border-color: oklch(0.131 0.015 151.4);
}

Tailwind CSS v4

@theme {
  --color-black-metal: #040905;
  --color-black-metal-50: #f2f6f3;
  --color-black-metal-100: #e4e9e5;
  --color-black-metal-200: #cfd6d1;
  --color-black-metal-300: #b2bab4;
  --color-black-metal-400: #98a19a;
  --color-black-metal-500: #7f8981;
  --color-black-metal-600: #6c746d;
  --color-black-metal-700: #565d57;
  --color-black-metal-800: #3f443f;
  --color-black-metal-900: #2b2f2c;
  --color-black-metal-950: #191b19;
}

SCSS

$black-metal: #040905;
$black-metal-rgb: 4, 9, 5;
$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);
}