#5172CC

CSS

:root {
  --skies-of-cyberspace: #5172cc;
  --skies-of-cyberspace-rgb: 81 114 204;
  --skies-of-cyberspace-oklch: oklch(0.572 0.144 266.7);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(224 55% 56%);
  border-color: oklch(0.572 0.144 266.7);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #5172cc;
  --color-skies-of-cyberspace-50: #e4f4ff;
  --color-skies-of-cyberspace-100: #d4e7ff;
  --color-skies-of-cyberspace-200: #bbd2ff;
  --color-skies-of-cyberspace-300: #99b4ff;
  --color-skies-of-cyberspace-400: #789af3;
  --color-skies-of-cyberspace-500: #5b7fe5;
  --color-skies-of-cyberspace-600: #4d6cc1;
  --color-skies-of-cyberspace-700: #3d579b;
  --color-skies-of-cyberspace-800: #294074;
  --color-skies-of-cyberspace-900: #1c2c52;
  --color-skies-of-cyberspace-950: #0c1937;
}

SCSS

$skies-of-cyberspace: #5172cc;
$skies-of-cyberspace-rgb: 81, 114, 204;
$skies-of-cyberspace-light: mix(#fff, $skies-of-cyberspace, 20%);
$skies-of-cyberspace-dark: mix(#000, $skies-of-cyberspace, 20%);

.element {
  color: $skies-of-cyberspace;
  box-shadow: 0 0 0 2px rgba($skies-of-cyberspace, 0.35);
}