#4A59AF

CSS

:root {
  --blasphemous-blue: #4a59af;
  --blasphemous-blue-rgb: 74 89 175;
  --blasphemous-blue-oklch: oklch(0.497 0.137 273);
}

.element {
  color: var(--blasphemous-blue);
  background-color: hsl(231 41% 49%);
  border-color: oklch(0.497 0.137 273);
}

Tailwind CSS v4

@theme {
  --color-blasphemous-blue: #4a59af;
  --color-blasphemous-blue-50: #e9f3ff;
  --color-blasphemous-blue-100: #dae5ff;
  --color-blasphemous-blue-200: #c3d0ff;
  --color-blasphemous-blue-300: #a3b2fd;
  --color-blasphemous-blue-400: #8498ef;
  --color-blasphemous-blue-500: #697de0;
  --color-blasphemous-blue-600: #596abd;
  --color-blasphemous-blue-700: #475598;
  --color-blasphemous-blue-800: #313e71;
  --color-blasphemous-blue-900: #212b50;
  --color-blasphemous-blue-950: #111835;
}

SCSS

$blasphemous-blue: #4a59af;
$blasphemous-blue-rgb: 74, 89, 175;
$blasphemous-blue-light: mix(#fff, $blasphemous-blue, 20%);
$blasphemous-blue-dark: mix(#000, $blasphemous-blue, 20%);

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