Transparent Blue

CSS

:root {
  --transparent-blue: #ddddff;
  --transparent-blue-rgb: 221 221 255;
  --transparent-blue-oklch: oklch(0.908 0.046 285.4);
}

.element {
  color: var(--transparent-blue);
  background-color: hsl(240 100% 93%);
  border-color: oklch(0.908 0.046 285.4);
}

Tailwind CSS v4

@theme {
  --color-transparent-blue: #ddddff;
  --color-transparent-blue-50: #f4f3ff;
  --color-transparent-blue-100: #e6e6f7;
  --color-transparent-blue-200: #d2d2e8;
  --color-transparent-blue-300: #b5b4ce;
  --color-transparent-blue-400: #9b9bb9;
  --color-transparent-blue-500: #8382a4;
  --color-transparent-blue-600: #6f6e8b;
  --color-transparent-blue-700: #58586f;
  --color-transparent-blue-800: #404052;
  --color-transparent-blue-900: #2c2c39;
  --color-transparent-blue-950: #191924;
}

SCSS

$transparent-blue: #ddddff;
$transparent-blue-rgb: 221, 221, 255;
$transparent-blue-light: mix(#fff, $transparent-blue, 20%);
$transparent-blue-dark: mix(#000, $transparent-blue, 20%);

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