#3C73D8

CSS

:root {
  --skies-of-cyberspace: #3c73d8;
  --skies-of-cyberspace-rgb: 60 115 216;
  --skies-of-cyberspace-oklch: oklch(0.572 0.166 261.3);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(219 67% 54%);
  border-color: oklch(0.572 0.166 261.3);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #3c73d8;
  --color-skies-of-cyberspace-50: #ddf6ff;
  --color-skies-of-cyberspace-100: #cbe8ff;
  --color-skies-of-cyberspace-200: #afd4ff;
  --color-skies-of-cyberspace-300: #8bb6ff;
  --color-skies-of-cyberspace-400: #659cff;
  --color-skies-of-cyberspace-500: #4380f2;
  --color-skies-of-cyberspace-600: #396dcc;
  --color-skies-of-cyberspace-700: #2d57a4;
  --color-skies-of-cyberspace-800: #1c407b;
  --color-skies-of-cyberspace-900: #122c57;
  --color-skies-of-cyberspace-950: #05193b;
}

SCSS

$skies-of-cyberspace: #3c73d8;
$skies-of-cyberspace-rgb: 60, 115, 216;
$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);
}