#6A6FAF

CSS

:root {
  --twinkle-night: #6a6faf;
  --twinkle-night-rgb: 106 111 175;
  --twinkle-night-oklch: oklch(0.565 0.099 279.3);
}

.element {
  color: var(--twinkle-night);
  background-color: hsl(236 30% 55%);
  border-color: oklch(0.565 0.099 279.3);
}

Tailwind CSS v4

@theme {
  --color-twinkle-night: #6a6faf;
  --color-twinkle-night-50: #f0f3ff;
  --color-twinkle-night-100: #e1e5ff;
  --color-twinkle-night-200: #ccd0fe;
  --color-twinkle-night-300: #aeb2e9;
  --color-twinkle-night-400: #9298d8;
  --color-twinkle-night-500: #797ec6;
  --color-twinkle-night-600: #666ba7;
  --color-twinkle-night-700: #525686;
  --color-twinkle-night-800: #3a3f64;
  --color-twinkle-night-900: #282b46;
  --color-twinkle-night-950: #16182e;
}

SCSS

$twinkle-night: #6a6faf;
$twinkle-night-rgb: 106, 111, 175;
$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);
}