#9AC0FF

CSS

:root {
  --pastel-blue: #9ac0ff;
  --pastel-blue-rgb: 154 192 255;
  --pastel-blue-oklch: oklch(0.804 0.099 260.3);
}

.element {
  color: var(--pastel-blue);
  background-color: hsl(217 100% 80%);
  border-color: oklch(0.804 0.099 260.3);
}

Tailwind CSS v4

@theme {
  --color-pastel-blue: #9ac0ff;
  --color-pastel-blue-50: #e6f6ff;
  --color-pastel-blue-100: #d6e9ff;
  --color-pastel-blue-200: #bed5ff;
  --color-pastel-blue-300: #9cb8eb;
  --color-pastel-blue-400: #7c9fd9;
  --color-pastel-blue-500: #5f86c7;
  --color-pastel-blue-600: #5172a8;
  --color-pastel-blue-700: #405b87;
  --color-pastel-blue-800: #2d4364;
  --color-pastel-blue-900: #1e2e46;
  --color-pastel-blue-950: #0e1b2e;
}

SCSS

$pastel-blue: #9ac0ff;
$pastel-blue-rgb: 154, 192, 255;
$pastel-blue-light: mix(#fff, $pastel-blue, 20%);
$pastel-blue-dark: mix(#000, $pastel-blue, 20%);

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