#33209C

CSS

:root {
  --gentian-blue: #33209c;
  --gentian-blue-rgb: 51 32 156;
  --gentian-blue-oklch: oklch(0.366 0.186 278.9);
}

.element {
  color: var(--gentian-blue);
  background-color: hsl(249 66% 37%);
  border-color: oklch(0.366 0.186 278.9);
}

Tailwind CSS v4

@theme {
  --color-gentian-blue: #33209c;
  --color-gentian-blue-50: #ebf0ff;
  --color-gentian-blue-100: #dce1ff;
  --color-gentian-blue-200: #c6cbff;
  --color-gentian-blue-300: #a7abff;
  --color-gentian-blue-400: #898eff;
  --color-gentian-blue-500: #7170fd;
  --color-gentian-blue-600: #5f5fd5;
  --color-gentian-blue-700: #4c4cab;
  --color-gentian-blue-800: #343881;
  --color-gentian-blue-900: #23265b;
  --color-gentian-blue-950: #13143e;
}

SCSS

$gentian-blue: #33209c;
$gentian-blue-rgb: 51, 32, 156;
$gentian-blue-light: mix(#fff, $gentian-blue, 20%);
$gentian-blue-dark: mix(#000, $gentian-blue, 20%);

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