#2E2639

CSS

:root {
  --black-velvet: #2e2639;
  --black-velvet-rgb: 46 38 57;
  --black-velvet-oklch: oklch(0.286 0.036 303.5);
}

.element {
  color: var(--black-velvet);
  background-color: hsl(265 20% 19%);
  border-color: oklch(0.286 0.036 303.5);
}

Tailwind CSS v4

@theme {
  --color-black-velvet: #2e2639;
  --color-black-velvet-50: #f7f3fe;
  --color-black-velvet-100: #ebe5f2;
  --color-black-velvet-200: #d8d1e1;
  --color-black-velvet-300: #bcb3c6;
  --color-black-velvet-400: #a39ab0;
  --color-black-velvet-500: #8b819a;
  --color-black-velvet-600: #766d82;
  --color-black-velvet-700: #5e5768;
  --color-black-velvet-800: #44404d;
  --color-black-velvet-900: #2f2c36;
  --color-black-velvet-950: #1c1921;
}

SCSS

$black-velvet: #2e2639;
$black-velvet-rgb: 46, 38, 57;
$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);
}