#4274D2

CSS

:root {
  --skies-of-cyberspace: #4274d2;
  --skies-of-cyberspace-rgb: 66 116 210;
  --skies-of-cyberspace-oklch: oklch(0.572 0.155 261.7);
}

.element {
  color: var(--skies-of-cyberspace);
  background-color: hsl(219 62% 54%);
  border-color: oklch(0.572 0.155 261.7);
}

Tailwind CSS v4

@theme {
  --color-skies-of-cyberspace: #4274d2;
  --color-skies-of-cyberspace-50: #dff6ff;
  --color-skies-of-cyberspace-100: #cee8ff;
  --color-skies-of-cyberspace-200: #b2d4ff;
  --color-skies-of-cyberspace-300: #8eb6ff;
  --color-skies-of-cyberspace-400: #6a9cf9;
  --color-skies-of-cyberspace-500: #4981eb;
  --color-skies-of-cyberspace-600: #3f6ec6;
  --color-skies-of-cyberspace-700: #32589f;
  --color-skies-of-cyberspace-800: #204177;
  --color-skies-of-cyberspace-900: #152d54;
  --color-skies-of-cyberspace-950: #061938;
}

SCSS

$skies-of-cyberspace: #4274d2;
$skies-of-cyberspace-rgb: 66, 116, 210;
$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);
}