#1476CF

CSS

:root {
  --fading-night: #1476cf;
  --fading-night-rgb: 20 118 207;
  --fading-night-oklch: oklch(0.562 0.16 252.2);
}

.element {
  color: var(--fading-night);
  background-color: hsl(209 82% 45%);
  border-color: oklch(0.562 0.16 252.2);
}

Tailwind CSS v4

@theme {
  --color-fading-night: #1476cf;
  --color-fading-night-50: #d6f8ff;
  --color-fading-night-100: #c4ebff;
  --color-fading-night-200: #a5d8ff;
  --color-fading-night-300: #7cbbff;
  --color-fading-night-400: #50a2fa;
  --color-fading-night-500: #1987ec;
  --color-fading-night-600: #1a73c7;
  --color-fading-night-700: #155ca0;
  --color-fading-night-800: #054477;
  --color-fading-night-900: #042f54;
  --color-fading-night-950: #001b38;
}

SCSS

$fading-night: #1476cf;
$fading-night-rgb: 20, 118, 207;
$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);
}