#110074

CSS

:root {
  --insomniac-blue: #110074;
  --insomniac-blue-rgb: 17 0 116;
  --insomniac-blue-oklch: oklch(0.26 0.17 270.5);
}

.element {
  color: var(--insomniac-blue);
  background-color: hsl(249 100% 23%);
  border-color: oklch(0.26 0.17 270.5);
}

Tailwind CSS v4

@theme {
  --color-insomniac-blue: #110074;
  --color-insomniac-blue-50: #e4f3ff;
  --color-insomniac-blue-100: #d4e5ff;
  --color-insomniac-blue-200: #bbd0ff;
  --color-insomniac-blue-300: #9ab1ff;
  --color-insomniac-blue-400: #7996ff;
  --color-insomniac-blue-500: #5d79f5;
  --color-insomniac-blue-600: #4f67cf;
  --color-insomniac-blue-700: #3f52a6;
  --color-insomniac-blue-800: #2a3d7c;
  --color-insomniac-blue-900: #1c2a58;
  --color-insomniac-blue-950: #0d173c;
}

SCSS

$insomniac-blue: #110074;
$insomniac-blue-rgb: 17, 0, 116;
$insomniac-blue-light: mix(#fff, $insomniac-blue, 20%);
$insomniac-blue-dark: mix(#000, $insomniac-blue, 20%);

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