#317394

CSS

:root {
  --harbour-blue: #317394;
  --harbour-blue-rgb: 49 115 148;
  --harbour-blue-oklch: oklch(0.528 0.084 233.3);
}

.element {
  color: var(--harbour-blue);
  background-color: hsl(200 50% 39%);
  border-color: oklch(0.528 0.084 233.3);
}

Tailwind CSS v4

@theme {
  --color-harbour-blue: #317394;
  --color-harbour-blue-50: #dffaff;
  --color-harbour-blue-100: #ceedff;
  --color-harbour-blue-200: #b2dbf4;
  --color-harbour-blue-300: #8dbfdd;
  --color-harbour-blue-400: #6aa7c9;
  --color-harbour-blue-500: #468fb5;
  --color-harbour-blue-600: #3c7999;
  --color-harbour-blue-700: #30617b;
  --color-harbour-blue-800: #20485a;
  --color-harbour-blue-900: #15323f;
  --color-harbour-blue-950: #061d28;
}

SCSS

$harbour-blue: #317394;
$harbour-blue-rgb: 49, 115, 148;
$harbour-blue-light: mix(#fff, $harbour-blue, 20%);
$harbour-blue-dark: mix(#000, $harbour-blue, 20%);

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