#1A52B8

CSS

:root {
  --blasphemous-blue: #1a52b8;
  --blasphemous-blue-rgb: 26 82 184;
  --blasphemous-blue-oklch: oklch(0.467 0.172 261.3);
}

.element {
  color: var(--blasphemous-blue);
  background-color: hsl(219 75% 41%);
  border-color: oklch(0.467 0.172 261.3);
}

Tailwind CSS v4

@theme {
  --color-blasphemous-blue: #1a52b8;
  --color-blasphemous-blue-50: #dcf6ff;
  --color-blasphemous-blue-100: #cae8ff;
  --color-blasphemous-blue-200: #aed4ff;
  --color-blasphemous-blue-300: #89b6ff;
  --color-blasphemous-blue-400: #629cff;
  --color-blasphemous-blue-500: #3f80f6;
  --color-blasphemous-blue-600: #376dcf;
  --color-blasphemous-blue-700: #2b57a7;
  --color-blasphemous-blue-800: #1a407d;
  --color-blasphemous-blue-900: #102c58;
  --color-blasphemous-blue-950: #04193c;
}

SCSS

$blasphemous-blue: #1a52b8;
$blasphemous-blue-rgb: 26, 82, 184;
$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);
}