#5D6A9B

CSS

:root {
  --twinkle-night: #5d6a9b;
  --twinkle-night-rgb: 93 106 155;
  --twinkle-night-oklch: oklch(0.534 0.079 272.1);
}

.element {
  color: var(--twinkle-night);
  background-color: hsl(227 25% 49%);
  border-color: oklch(0.534 0.079 272.1);
}

Tailwind CSS v4

@theme {
  --color-twinkle-night: #5d6a9b;
  --color-twinkle-night-50: #eef4ff;
  --color-twinkle-night-100: #dfe7ff;
  --color-twinkle-night-200: #c9d3f7;
  --color-twinkle-night-300: #abb5e0;
  --color-twinkle-night-400: #8e9cce;
  --color-twinkle-night-500: #7483bb;
  --color-twinkle-night-600: #626f9e;
  --color-twinkle-night-700: #4e597f;
  --color-twinkle-night-800: #38415e;
  --color-twinkle-night-900: #262d42;
  --color-twinkle-night-950: #151a2a;
}

SCSS

$twinkle-night: #5d6a9b;
$twinkle-night-rgb: 93, 106, 155;
$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);
}