#4B72C6

CSS

:root {
  --skies-of-cyberspace: #4b72c6;
  --skies-of-cyberspace-rgb: 75 114 198;
  --skies-of-cyberspace-oklch: oklch(0.565 0.137 263.8);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(221 52% 54%);
  border-color: oklch(0.565 0.137 263.8);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #4b72c6;
  --color-skies-of-cyberspace-50: #e3f5ff;
  --color-skies-of-cyberspace-100: #d2e8ff;
  --color-skies-of-cyberspace-200: #b9d4ff;
  --color-skies-of-cyberspace-300: #96b6fe;
  --color-skies-of-cyberspace-400: #749cf0;
  --color-skies-of-cyberspace-500: #5682e0;
  --color-skies-of-cyberspace-600: #496ebd;
  --color-skies-of-cyberspace-700: #3a5898;
  --color-skies-of-cyberspace-800: #274171;
  --color-skies-of-cyberspace-900: #1a2d50;
  --color-skies-of-cyberspace-950: #0b1935;
}

SCSS

$skies-of-cyberspace: #4b72c6;
$skies-of-cyberspace-rgb: 75, 114, 198;
$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);
}