#5B63C3

CSS

:root {
  --savoy-blue: #5b63c3;
  --savoy-blue-rgb: 91 99 195;
  --savoy-blue-oklch: oklch(0.542 0.148 276.7);
}

.element {
  color: var(--savoy-blue);
  background-color: hsl(235 46% 56%);
  border-color: oklch(0.542 0.148 276.7);
}

Tailwind CSS v4

@theme {
  --color-savoy-blue: #5b63c3;
  --color-savoy-blue-50: #ebf2ff;
  --color-savoy-blue-100: #dce4ff;
  --color-savoy-blue-200: #c6ceff;
  --color-savoy-blue-300: #a7afff;
  --color-savoy-blue-400: #8995f4;
  --color-savoy-blue-500: #6f79e6;
  --color-savoy-blue-600: #5e67c2;
  --color-savoy-blue-700: #4b529c;
  --color-savoy-blue-800: #343c75;
  --color-savoy-blue-900: #232952;
  --color-savoy-blue-950: #131737;
}

SCSS

$savoy-blue: #5b63c3;
$savoy-blue-rgb: 91, 99, 195;
$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);
}