#2076CB

CSS

:root {
  --fading-night: #2076cb;
  --fading-night-rgb: 32 118 203;
  --fading-night-oklch: oklch(0.561 0.153 252.5);
}

.element {
  color: var(--fading-night);
  background-color: hsl(210 73% 46%);
  border-color: oklch(0.561 0.153 252.5);
}

Tailwind CSS v4

@theme {
  --color-fading-night: #2076cb;
  --color-fading-night-50: #d8f8ff;
  --color-fading-night-100: #c6ebff;
  --color-fading-night-200: #a7d8ff;
  --color-fading-night-300: #80bbff;
  --color-fading-night-400: #55a2f6;
  --color-fading-night-500: #2788e7;
  --color-fading-night-600: #2473c3;
  --color-fading-night-700: #1c5c9d;
  --color-fading-night-800: #0d4475;
  --color-fading-night-900: #082f52;
  --color-fading-night-950: #001b37;
}

SCSS

$fading-night: #2076cb;
$fading-night-rgb: 32, 118, 203;
$fading-night-light: mix(#fff, $fading-night, 20%);
$fading-night-dark: mix(#000, $fading-night, 20%);

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