#6D72A8

CSS

:root {
  --twinkle-night: #6d72a8;
  --twinkle-night-rgb: 109 114 168;
  --twinkle-night-oklch: oklch(0.57 0.083 279.3);
}

.element {
  color: var(--twinkle-night);
  background-color: hsl(235 25% 54%);
  border-color: oklch(0.57 0.083 279.3);
}

Tailwind CSS v4

@theme {
  --color-twinkle-night: #6d72a8;
  --color-twinkle-night-50: #f0f3ff;
  --color-twinkle-night-100: #e2e5ff;
  --color-twinkle-night-200: #cdd1f8;
  --color-twinkle-night-300: #afb3e2;
  --color-twinkle-night-400: #949acf;
  --color-twinkle-night-500: #7b80bd;
  --color-twinkle-night-600: #686d9f;
  --color-twinkle-night-700: #535780;
  --color-twinkle-night-800: #3b405f;
  --color-twinkle-night-900: #292c43;
  --color-twinkle-night-950: #17192b;
}

SCSS

$twinkle-night: #6d72a8;
$twinkle-night-rgb: 109, 114, 168;
$twinkle-night-light: mix(#fff, $twinkle-night, 20%);
$twinkle-night-dark: mix(#000, $twinkle-night, 20%);

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