#5164C7

CSS

:root {
  --savoy-blue: #5164c7;
  --savoy-blue-rgb: 81 100 199;
  --savoy-blue-oklch: oklch(0.54 0.154 272.1);
}

.element {
  color: var(--savoy-blue);
  background-color: hsl(230 51% 55%);
  border-color: oklch(0.54 0.154 272.1);
}

Tailwind CSS v4

@theme {
  --color-savoy-blue: #5164c7;
  --color-savoy-blue-50: #e7f3ff;
  --color-savoy-blue-100: #d7e5ff;
  --color-savoy-blue-200: #bfd0ff;
  --color-savoy-blue-300: #9fb1ff;
  --color-savoy-blue-400: #7f97f9;
  --color-savoy-blue-500: #647beb;
  --color-savoy-blue-600: #5568c6;
  --color-savoy-blue-700: #44539f;
  --color-savoy-blue-800: #2e3d77;
  --color-savoy-blue-900: #1f2a54;
  --color-savoy-blue-950: #0f1739;
}

SCSS

$savoy-blue: #5164c7;
$savoy-blue-rgb: 81, 100, 199;
$savoy-blue-light: mix(#fff, $savoy-blue, 20%);
$savoy-blue-dark: mix(#000, $savoy-blue, 20%);

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