#5665BF

CSS

:root {
  --savoy-blue: #5665bf;
  --savoy-blue-rgb: 86 101 191;
  --savoy-blue-oklch: oklch(0.54 0.14 273.7);
}

.element {
  color: var(--savoy-blue);
  background-color: hsl(231 45% 54%);
  border-color: oklch(0.54 0.14 273.7);
}

Tailwind CSS v4

@theme {
  --color-savoy-blue: #5665bf;
  --color-savoy-blue-50: #e9f3ff;
  --color-savoy-blue-100: #dae5ff;
  --color-savoy-blue-200: #c3d0ff;
  --color-savoy-blue-300: #a3b1ff;
  --color-savoy-blue-400: #8497f1;
  --color-savoy-blue-500: #6a7ce2;
  --color-savoy-blue-600: #5a69bf;
  --color-savoy-blue-700: #485499;
  --color-savoy-blue-800: #313e73;
  --color-savoy-blue-900: #212a51;
  --color-savoy-blue-950: #111836;
}

SCSS

$savoy-blue: #5665bf;
$savoy-blue-rgb: 86, 101, 191;
$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);
}