#002632

CSS

:root {
  --black-box: #002632;
  --black-box-rgb: 0 38 50;
  --black-box-oklch: oklch(0.25 0.047 223.9);
}

.element {
  color: var(--black-box);
  background-color: hsl(194 100% 10%);
  border-color: oklch(0.25 0.047 223.9);
}

Tailwind CSS v4

@theme {
  --color-black-box: #002632;
  --color-black-box-50: #e8f8ff;
  --color-black-box-100: #d8ecf4;
  --color-black-box-200: #c0d9e4;
  --color-black-box-300: #9fbdca;
  --color-black-box-400: #81a5b3;
  --color-black-box-500: #648d9d;
  --color-black-box-600: #557885;
  --color-black-box-700: #44606b;
  --color-black-box-800: #30464e;
  --color-black-box-900: #213136;
  --color-black-box-950: #101d21;
}

SCSS

$black-box: #002632;
$black-box-rgb: 0, 38, 50;
$black-box-light: mix(#fff, $black-box, 20%);
$black-box-dark: mix(#000, $black-box, 20%);

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