#2F4050

CSS

:root {
  --depths-of-the-nile: #2f4050;
  --depths-of-the-nile-rgb: 47 64 80;
  --depths-of-the-nile-oklch: oklch(0.364 0.035 247.3);
}

.element {
  color: var(--depths-of-the-nile);
  background-color: hsl(209 26% 25%);
  border-color: oklch(0.364 0.035 247.3);
}

Tailwind CSS v4

@theme {
  --color-depths-of-the-nile: #2f4050;
  --color-depths-of-the-nile-50: #eef6ff;
  --color-depths-of-the-nile-100: #dfe9f4;
  --color-depths-of-the-nile-200: #c9d6e3;
  --color-depths-of-the-nile-300: #aab9c9;
  --color-depths-of-the-nile-400: #8ea1b3;
  --color-depths-of-the-nile-500: #74899d;
  --color-depths-of-the-nile-600: #627485;
  --color-depths-of-the-nile-700: #4e5d6a;
  --color-depths-of-the-nile-800: #38444e;
  --color-depths-of-the-nile-900: #272f36;
  --color-depths-of-the-nile-950: #151b21;
}

SCSS

$depths-of-the-nile: #2f4050;
$depths-of-the-nile-rgb: 47, 64, 80;
$depths-of-the-nile-light: mix(#fff, $depths-of-the-nile, 20%);
$depths-of-the-nile-dark: mix(#000, $depths-of-the-nile, 20%);

.element {
  color: $depths-of-the-nile;
  box-shadow: 0 0 0 2px rgba($depths-of-the-nile, 0.35);
}