#0A0E13

CSS

:root {
  --eight-ball: #0a0e13;
  --eight-ball-rgb: 10 14 19;
  --eight-ball-oklch: oklch(0.162 0.012 254.2);
}

.element {
  color: var(--eight-ball);
  background-color: hsl(213 31% 6%);
  border-color: oklch(0.162 0.012 254.2);
}

Tailwind CSS v4

@theme {
  --color-eight-ball: #0a0e13;
  --color-eight-ball-50: #f3f5f9;
  --color-eight-ball-100: #e5e8ec;
  --color-eight-ball-200: #d1d4da;
  --color-eight-ball-300: #b3b8be;
  --color-eight-ball-400: #999fa6;
  --color-eight-ball-500: #81878e;
  --color-eight-ball-600: #6d7279;
  --color-eight-ball-700: #575b60;
  --color-eight-ball-800: #3f4347;
  --color-eight-ball-900: #2c2e31;
  --color-eight-ball-950: #191b1d;
}

SCSS

$eight-ball: #0a0e13;
$eight-ball-rgb: 10, 14, 19;
$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);
}