#1634A4

CSS

:root {
  --blue-hour: #1634a4;
  --blue-hour-rgb: 22 52 164;
  --blue-hour-oklch: oklch(0.389 0.182 265.8);
}

.element {
  color: var(--blue-hour);
  background-color: hsl(227 76% 36%);
  border-color: oklch(0.389 0.182 265.8);
}

Tailwind CSS v4

@theme {
  --color-blue-hour: #1634a4;
  --color-blue-hour-50: #def4ff;
  --color-blue-hour-100: #cde7ff;
  --color-blue-hour-200: #b2d2ff;
  --color-blue-hour-300: #8fb3ff;
  --color-blue-hour-400: #6b98ff;
  --color-blue-hour-500: #4c7bfd;
  --color-blue-hour-600: #4168d5;
  --color-blue-hour-700: #3354ac;
  --color-blue-hour-800: #203e80;
  --color-blue-hour-900: #152a5b;
  --color-blue-hour-950: #07173e;
}

SCSS

$blue-hour: #1634a4;
$blue-hour-rgb: 22, 52, 164;
$blue-hour-light: mix(#fff, $blue-hour, 20%);
$blue-hour-dark: mix(#000, $blue-hour, 20%);

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