#0F163B

CSS

:root {
  --infinite-night: #0f163b;
  --infinite-night-rgb: 15 22 59;
  --infinite-night-oklch: oklch(0.219 0.072 271.2);
}

.element {
  color: var(--infinite-night);
  background-color: hsl(230 59% 15%);
  border-color: oklch(0.219 0.072 271.2);
}

Tailwind CSS v4

@theme {
  --color-infinite-night: #0f163b;
  --color-infinite-night-50: #eef4ff;
  --color-infinite-night-100: #e0e7ff;
  --color-infinite-night-200: #cad3f4;
  --color-infinite-night-300: #abb6dd;
  --color-infinite-night-400: #8f9dca;
  --color-infinite-night-500: #7584b6;
  --color-infinite-night-600: #636f9a;
  --color-infinite-night-700: #4f597b;
  --color-infinite-night-800: #38415c;
  --color-infinite-night-900: #262d40;
  --color-infinite-night-950: #151a29;
}

SCSS

$infinite-night: #0f163b;
$infinite-night-rgb: 15, 22, 59;
$infinite-night-light: mix(#fff, $infinite-night, 20%);
$infinite-night-dark: mix(#000, $infinite-night, 20%);

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