#0064FF

CSS

:root {
  --blue-ribbon: #0064ff;
  --blue-ribbon-rgb: 0 100 255;
  --blue-ribbon-oklch: oklch(0.56 0.243 261.1);
}

.element {
  color: var(--blue-ribbon);
  background-color: hsl(216 100% 50%);
  border-color: oklch(0.56 0.243 261.1);
}

Tailwind CSS v4

@theme {
  --color-blue-ribbon: #0064ff;
  --color-blue-ribbon-50: #d1f6ff;
  --color-blue-ribbon-100: #bde8ff;
  --color-blue-ribbon-200: #9dd2ff;
  --color-blue-ribbon-300: #73b2ff;
  --color-blue-ribbon-400: #4295ff;
  --color-blue-ribbon-500: #0374ff;
  --color-blue-ribbon-600: #0a63f5;
  --color-blue-ribbon-700: #094fc5;
  --color-blue-ribbon-800: #003b94;
  --color-blue-ribbon-900: #002969;
  --color-blue-ribbon-950: #001549;
}

SCSS

$blue-ribbon: #0064ff;
$blue-ribbon-rgb: 0, 100, 255;
$blue-ribbon-light: mix(#fff, $blue-ribbon, 20%);
$blue-ribbon-dark: mix(#000, $blue-ribbon, 20%);

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