#4E71D3

CSS

:root {
  --skies-of-cyberspace: #4e71d3;
  --skies-of-cyberspace-rgb: 78 113 211;
  --skies-of-cyberspace-oklch: oklch(0.572 0.156 266.7);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(224 60% 57%);
  border-color: oklch(0.572 0.156 266.7);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #4e71d3;
  --color-skies-of-cyberspace-50: #e2f4ff;
  --color-skies-of-cyberspace-100: #d2e7ff;
  --color-skies-of-cyberspace-200: #b9d2ff;
  --color-skies-of-cyberspace-300: #96b4ff;
  --color-skies-of-cyberspace-400: #749afa;
  --color-skies-of-cyberspace-500: #577eec;
  --color-skies-of-cyberspace-600: #4a6bc7;
  --color-skies-of-cyberspace-700: #3b56a0;
  --color-skies-of-cyberspace-800: #273f78;
  --color-skies-of-cyberspace-900: #1a2b54;
  --color-skies-of-cyberspace-950: #0b1839;
}

SCSS

$skies-of-cyberspace: #4e71d3;
$skies-of-cyberspace-rgb: 78, 113, 211;
$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);
}