#106FBC

CSS

:root {
  --french-blue: #106fbc;
  --french-blue-rgb: 16 111 188;
  --french-blue-oklch: oklch(0.533 0.145 250.1);
}

.element {
  color: var(--french-blue);
  background-color: hsl(207 84% 40%);
  border-color: oklch(0.533 0.145 250.1);
}

Tailwind CSS v4

@theme {
  --color-french-blue: #106fbc;
  --color-french-blue-50: #d8f9ff;
  --color-french-blue-100: #c6ecff;
  --color-french-blue-200: #a7d9ff;
  --color-french-blue-300: #7fbcff;
  --color-french-blue-400: #55a3f0;
  --color-french-blue-500: #2589e1;
  --color-french-blue-600: #2275be;
  --color-french-blue-700: #1b5d99;
  --color-french-blue-800: #0c4571;
  --color-french-blue-900: #083050;
  --color-french-blue-950: #001c35;
}

SCSS

$french-blue: #106fbc;
$french-blue-rgb: 16, 111, 188;
$french-blue-light: mix(#fff, $french-blue, 20%);
$french-blue-dark: mix(#000, $french-blue, 20%);

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