#0079FF

CSS

:root {
  --hadfield-blue: #0079ff;
  --hadfield-blue-rgb: 0 121 255;
  --hadfield-blue-oklch: oklch(0.601 0.219 257.6);
}

.element {
  color: var(--hadfield-blue);
  background-color: hsl(212 100% 50%);
  border-color: oklch(0.601 0.219 257.6);
}

Tailwind CSS v4

@theme {
  --color-hadfield-blue: #0079ff;
  --color-hadfield-blue-50: #d0f7ff;
  --color-hadfield-blue-100: #bdeaff;
  --color-hadfield-blue-200: #9cd5ff;
  --color-hadfield-blue-300: #71b6ff;
  --color-hadfield-blue-400: #3d9bff;
  --color-hadfield-blue-500: #007cff;
  --color-hadfield-blue-600: #006ae7;
  --color-hadfield-blue-700: #0055ba;
  --color-hadfield-blue-800: #003f8b;
  --color-hadfield-blue-900: #002b63;
  --color-hadfield-blue-950: #001844;
}

SCSS

$hadfield-blue: #0079ff;
$hadfield-blue-rgb: 0, 121, 255;
$hadfield-blue-light: mix(#fff, $hadfield-blue, 20%);
$hadfield-blue-dark: mix(#000, $hadfield-blue, 20%);

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