Old World

CSS

:root {
  --old-world: #91a8cf;
  --old-world-rgb: 145 168 207;
  --old-world-oklch: oklch(0.728 0.063 260.9);
}

.element {
  color: var(--old-world);
  background-color: hsl(218 39% 69%);
  border-color: oklch(0.728 0.063 260.9);
}

Tailwind CSS v4

@theme {
  --color-old-world: #91a8cf;
  --color-old-world-50: #ecf6ff;
  --color-old-world-100: #dde8fe;
  --color-old-world-200: #c6d5f0;
  --color-old-world-300: #a7b8d8;
  --color-old-world-400: #8a9fc4;
  --color-old-world-500: #6f87b0;
  --color-old-world-600: #5e7295;
  --color-old-world-700: #4b5b77;
  --color-old-world-800: #354358;
  --color-old-world-900: #242e3e;
  --color-old-world-950: #131b27;
}

SCSS

$old-world: #91a8cf;
$old-world-rgb: 145, 168, 207;
$old-world-light: mix(#fff, $old-world, 20%);
$old-world-dark: mix(#000, $old-world, 20%);

.element {
  color: $old-world;
  box-shadow: 0 0 0 2px rgba($old-world, 0.35);
}