#4A72C7

CSS

:root {
  --skies-of-cyberspace: #4a72c7;
  --skies-of-cyberspace-rgb: 74 114 199;
  --skies-of-cyberspace-oklch: oklch(0.565 0.139 263.6);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(221 53% 54%);
  border-color: oklch(0.565 0.139 263.6);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #4a72c7;
  --color-skies-of-cyberspace-50: #e2f5ff;
  --color-skies-of-cyberspace-100: #d2e8ff;
  --color-skies-of-cyberspace-200: #b8d4ff;
  --color-skies-of-cyberspace-300: #95b6ff;
  --color-skies-of-cyberspace-400: #739cf1;
  --color-skies-of-cyberspace-500: #5582e2;
  --color-skies-of-cyberspace-600: #486ebe;
  --color-skies-of-cyberspace-700: #395899;
  --color-skies-of-cyberspace-800: #264172;
  --color-skies-of-cyberspace-900: #192d50;
  --color-skies-of-cyberspace-950: #0a1936;
}

SCSS

$skies-of-cyberspace: #4a72c7;
$skies-of-cyberspace-rgb: 74, 114, 199;
$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);
}