#2B70E3

CSS

:root {
  --skies-of-cyberspace: #2b70e3;
  --skies-of-cyberspace-rgb: 43 112 227;
  --skies-of-cyberspace-oklch: oklch(0.568 0.188 260.2);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(218 77% 53%);
  border-color: oklch(0.568 0.188 260.2);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #2b70e3;
  --color-skies-of-cyberspace-50: #d8f6ff;
  --color-skies-of-cyberspace-100: #c6e9ff;
  --color-skies-of-cyberspace-200: #a8d4ff;
  --color-skies-of-cyberspace-300: #82b6ff;
  --color-skies-of-cyberspace-400: #589bff;
  --color-skies-of-cyberspace-500: #317fff;
  --color-skies-of-cyberspace-600: #2b6cd8;
  --color-skies-of-cyberspace-700: #2256ae;
  --color-skies-of-cyberspace-800: #104082;
  --color-skies-of-cyberspace-900: #0a2c5c;
  --color-skies-of-cyberspace-950: #01183f;
}

SCSS

$skies-of-cyberspace: #2b70e3;
$skies-of-cyberspace-rgb: 43, 112, 227;
$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);
}