#4C71D5

CSS

:root {
  --skies-of-cyberspace: #4c71d5;
  --skies-of-cyberspace-rgb: 76 113 213;
  --skies-of-cyberspace-oklch: oklch(0.573 0.159 266.2);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(224 62% 57%);
  border-color: oklch(0.573 0.159 266.2);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #4c71d5;
  --color-skies-of-cyberspace-50: #e2f4ff;
  --color-skies-of-cyberspace-100: #d1e7ff;
  --color-skies-of-cyberspace-200: #b7d2ff;
  --color-skies-of-cyberspace-300: #95b4ff;
  --color-skies-of-cyberspace-400: #729afc;
  --color-skies-of-cyberspace-500: #557eee;
  --color-skies-of-cyberspace-600: #486bc9;
  --color-skies-of-cyberspace-700: #3956a2;
  --color-skies-of-cyberspace-800: #263f79;
  --color-skies-of-cyberspace-900: #192b55;
  --color-skies-of-cyberspace-950: #0a1839;
}

SCSS

$skies-of-cyberspace: #4c71d5;
$skies-of-cyberspace-rgb: 76, 113, 213;
$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);
}