#6B6FB1

CSS

:root {
  --twinkle-night: #6b6fb1;
  --twinkle-night-rgb: 107 111 177;
  --twinkle-night-oklch: oklch(0.567 0.101 280);
}

.element {
  color: var(--twinkle-night);
  background-color: hsl(237 31% 56%);
  border-color: oklch(0.567 0.101 280);
}

Tailwind CSS v4

@theme {
  --color-twinkle-night: #6b6fb1;
  --color-twinkle-night-50: #f0f2ff;
  --color-twinkle-night-100: #e2e5ff;
  --color-twinkle-night-200: #cdd0ff;
  --color-twinkle-night-300: #afb2eb;
  --color-twinkle-night-400: #9298da;
  --color-twinkle-night-500: #797ec8;
  --color-twinkle-night-600: #676ba9;
  --color-twinkle-night-700: #525588;
  --color-twinkle-night-800: #3a3e65;
  --color-twinkle-night-900: #282b47;
  --color-twinkle-night-950: #16182e;
}

SCSS

$twinkle-night: #6b6fb1;
$twinkle-night-rgb: 107, 111, 177;
$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);
}