#0E6FB9

CSS

:root {
  --french-blue: #0e6fb9;
  --french-blue-rgb: 14 111 185;
  --french-blue-oklch: oklch(0.531 0.141 249);
}

.element {
  color: var(--french-blue);
  background-color: hsl(206 86% 39%);
  border-color: oklch(0.531 0.141 249);
}

Tailwind CSS v4

@theme {
  --color-french-blue: #0e6fb9;
  --color-french-blue-50: #d8f9ff;
  --color-french-blue-100: #c6ecff;
  --color-french-blue-200: #a7d9ff;
  --color-french-blue-300: #7fbcfd;
  --color-french-blue-400: #55a4ee;
  --color-french-blue-500: #258ade;
  --color-french-blue-600: #2275bc;
  --color-french-blue-700: #1b5e97;
  --color-french-blue-800: #0c4570;
  --color-french-blue-900: #08304f;
  --color-french-blue-950: #001c35;
}

SCSS

$french-blue: #0e6fb9;
$french-blue-rgb: 14, 111, 185;
$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);
}