#4771CC

CSS

:root {
  --skies-of-cyberspace: #4771cc;
  --skies-of-cyberspace-rgb: 71 113 204;
  --skies-of-cyberspace-oklch: oklch(0.564 0.148 263.7);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(221 57% 54%);
  border-color: oklch(0.564 0.148 263.7);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #4771cc;
  --color-skies-of-cyberspace-50: #e1f5ff;
  --color-skies-of-cyberspace-100: #d0e8ff;
  --color-skies-of-cyberspace-200: #b6d3ff;
  --color-skies-of-cyberspace-300: #93b5ff;
  --color-skies-of-cyberspace-400: #709cf6;
  --color-skies-of-cyberspace-500: #5281e7;
  --color-skies-of-cyberspace-600: #466dc3;
  --color-skies-of-cyberspace-700: #37579d;
  --color-skies-of-cyberspace-800: #244075;
  --color-skies-of-cyberspace-900: #182c53;
  --color-skies-of-cyberspace-950: #091937;
}

SCSS

$skies-of-cyberspace: #4771cc;
$skies-of-cyberspace-rgb: 71, 113, 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);
}