#4372CE

CSS

:root {
  --skies-of-cyberspace: #4372ce;
  --skies-of-cyberspace-rgb: 67 114 206;
  --skies-of-cyberspace-oklch: oklch(0.566 0.151 262.3);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(220 59% 54%);
  border-color: oklch(0.566 0.151 262.3);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #4372ce;
  --color-skies-of-cyberspace-50: #e0f6ff;
  --color-skies-of-cyberspace-100: #cfe8ff;
  --color-skies-of-cyberspace-200: #b4d4ff;
  --color-skies-of-cyberspace-300: #90b6ff;
  --color-skies-of-cyberspace-400: #6d9cf7;
  --color-skies-of-cyberspace-500: #4d81e9;
  --color-skies-of-cyberspace-600: #416ec4;
  --color-skies-of-cyberspace-700: #34589e;
  --color-skies-of-cyberspace-800: #214176;
  --color-skies-of-cyberspace-900: #162d53;
  --color-skies-of-cyberspace-950: #071938;
}

SCSS

$skies-of-cyberspace: #4372ce;
$skies-of-cyberspace-rgb: 67, 114, 206;
$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);
}