#4C71CB

CSS

:root {
  --skies-of-cyberspace: #4c71cb;
  --skies-of-cyberspace-rgb: 76 113 203;
  --skies-of-cyberspace-oklch: oklch(0.566 0.145 265.3);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(223 55% 55%);
  border-color: oklch(0.566 0.145 265.3);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #4c71cb;
  --color-skies-of-cyberspace-50: #e3f5ff;
  --color-skies-of-cyberspace-100: #d2e7ff;
  --color-skies-of-cyberspace-200: #b9d3ff;
  --color-skies-of-cyberspace-300: #96b5ff;
  --color-skies-of-cyberspace-400: #749bf4;
  --color-skies-of-cyberspace-500: #5780e5;
  --color-skies-of-cyberspace-600: #4a6dc2;
  --color-skies-of-cyberspace-700: #3b579c;
  --color-skies-of-cyberspace-800: #274074;
  --color-skies-of-cyberspace-900: #1a2c52;
  --color-skies-of-cyberspace-950: #0b1937;
}

SCSS

$skies-of-cyberspace: #4c71cb;
$skies-of-cyberspace-rgb: 76, 113, 203;
$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);
}