Black of Night

CSS

:root {
  --black-of-night: #323639;
  --black-of-night-rgb: 50 54 57;
  --black-of-night-oklch: oklch(0.33 0.008 240.1);
}

.element {
  color: var(--black-of-night);
  background-color: hsl(206 7% 21%);
  border-color: oklch(0.33 0.008 240.1);
}

Tailwind CSS v4

@theme {
  --color-black-of-night: #323639;
  --color-black-of-night-50: #f3f5f7;
  --color-black-of-night-100: #e6e8ea;
  --color-black-of-night-200: #d1d5d7;
  --color-black-of-night-300: #b4b8bb;
  --color-black-of-night-400: #9a9fa2;
  --color-black-of-night-500: #82878b;
  --color-black-of-night-600: #6e7275;
  --color-black-of-night-700: #585b5e;
  --color-black-of-night-800: #404345;
  --color-black-of-night-900: #2c2e2f;
  --color-black-of-night-950: #191b1c;
}

SCSS

$black-of-night: #323639;
$black-of-night-rgb: 50, 54, 57;
$black-of-night-light: mix(#fff, $black-of-night, 20%);
$black-of-night-dark: mix(#000, $black-of-night, 20%);

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