#221F2C

CSS

:root {
  --black-velvet: #221f2c;
  --black-velvet-rgb: 34 31 44;
  --black-velvet-oklch: oklch(0.249 0.025 295.1);
}

.element {
  color: var(--black-velvet);
  background-color: hsl(254 17% 15%);
  border-color: oklch(0.249 0.025 295.1);
}

Tailwind CSS v4

@theme {
  --color-black-velvet: #221f2c;
  --color-black-velvet-50: #f6f4fc;
  --color-black-velvet-100: #e8e6ef;
  --color-black-velvet-200: #d5d2de;
  --color-black-velvet-300: #b8b5c3;
  --color-black-velvet-400: #9f9cac;
  --color-black-velvet-500: #878395;
  --color-black-velvet-600: #726f7e;
  --color-black-velvet-700: #5b5965;
  --color-black-velvet-800: #42414a;
  --color-black-velvet-900: #2e2d34;
  --color-black-velvet-950: #1b1a1f;
}

SCSS

$black-velvet: #221f2c;
$black-velvet-rgb: 34, 31, 44;
$black-velvet-light: mix(#fff, $black-velvet, 20%);
$black-velvet-dark: mix(#000, $black-velvet, 20%);

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