#010705

CSS

:root {
  --black-hole: #010705;
  --black-hole-rgb: 1 7 5;
  --black-hole-oklch: oklch(0.117 0.018 174.9);
}

.element {
  color: var(--black-hole);
  background-color: hsl(160 75% 2%);
  border-color: oklch(0.117 0.018 174.9);
}

Tailwind CSS v4

@theme {
  --color-black-hole: #010705;
  --color-black-hole-50: #f0f7f5;
  --color-black-hole-100: #e2eae8;
  --color-black-hole-200: #cdd7d4;
  --color-black-hole-300: #aebab7;
  --color-black-hole-400: #94a29e;
  --color-black-hole-500: #7b8a85;
  --color-black-hole-600: #687571;
  --color-black-hole-700: #535e5a;
  --color-black-hole-800: #3c4442;
  --color-black-hole-900: #2a2f2d;
  --color-black-hole-950: #171c1a;
}

SCSS

$black-hole: #010705;
$black-hole-rgb: 1, 7, 5;
$black-hole-light: mix(#fff, $black-hole, 20%);
$black-hole-dark: mix(#000, $black-hole, 20%);

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