#004F83

CSS

:root {
  --dark-denim: #004f83;
  --dark-denim-rgb: 0 79 131;
  --dark-denim-oklch: oklch(0.416 0.109 246.8);
}

.element {
  color: var(--dark-denim);
  background-color: hsl(204 100% 26%);
  border-color: oklch(0.416 0.109 246.8);
}

Tailwind CSS v4

@theme {
  --color-dark-denim: #004f83;
  --color-dark-denim-50: #def9ff;
  --color-dark-denim-100: #cdecff;
  --color-dark-denim-200: #b1d9ff;
  --color-dark-denim-300: #8bbced;
  --color-dark-denim-400: #67a4db;
  --color-dark-denim-500: #428cca;
  --color-dark-denim-600: #3976aa;
  --color-dark-denim-700: #2d5f89;
  --color-dark-denim-800: #1d4665;
  --color-dark-denim-900: #133047;
  --color-dark-denim-950: #051c2e;
}

SCSS

$dark-denim: #004f83;
$dark-denim-rgb: 0, 79, 131;
$dark-denim-light: mix(#fff, $dark-denim, 20%);
$dark-denim-dark: mix(#000, $dark-denim, 20%);

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