#03080D

CSS

:root {
  --eight-ball: #03080d;
  --eight-ball-rgb: 3 8 13;
  --eight-ball-oklch: oklch(0.13 0.016 240.2);
}

.element {
  color: var(--eight-ball);
  background-color: hsl(210 63% 3%);
  border-color: oklch(0.13 0.016 240.2);
}

Tailwind CSS v4

@theme {
  --color-eight-ball: #03080d;
  --color-eight-ball-50: #f1f6f9;
  --color-eight-ball-100: #e3e9ed;
  --color-eight-ball-200: #ced5db;
  --color-eight-ball-300: #b0b9bf;
  --color-eight-ball-400: #96a0a7;
  --color-eight-ball-500: #7d8890;
  --color-eight-ball-600: #6a737a;
  --color-eight-ball-700: #545c62;
  --color-eight-ball-800: #3d4347;
  --color-eight-ball-900: #2a2e31;
  --color-eight-ball-950: #181b1d;
}

SCSS

$eight-ball: #03080d;
$eight-ball-rgb: 3, 8, 13;
$eight-ball-light: mix(#fff, $eight-ball, 20%);
$eight-ball-dark: mix(#000, $eight-ball, 20%);

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