#5172CF

CSS

:root {
  --skies-of-cyberspace: #5172cf;
  --skies-of-cyberspace-rgb: 81 114 207;
  --skies-of-cyberspace-oklch: oklch(0.574 0.148 267);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(224 57% 56%);
  border-color: oklch(0.574 0.148 267);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #5172cf;
  --color-skies-of-cyberspace-50: #e4f4ff;
  --color-skies-of-cyberspace-100: #d3e7ff;
  --color-skies-of-cyberspace-200: #bad2ff;
  --color-skies-of-cyberspace-300: #98b4ff;
  --color-skies-of-cyberspace-400: #779af6;
  --color-skies-of-cyberspace-500: #5a7fe7;
  --color-skies-of-cyberspace-600: #4c6cc3;
  --color-skies-of-cyberspace-700: #3d569d;
  --color-skies-of-cyberspace-800: #293f75;
  --color-skies-of-cyberspace-900: #1b2c53;
  --color-skies-of-cyberspace-950: #0c1837;
}

SCSS

$skies-of-cyberspace: #5172cf;
$skies-of-cyberspace-rgb: 81, 114, 207;
$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);
}