#617C76

CSS

:root {
  --underwater-world: #617c76;
  --underwater-world-rgb: 97 124 118;
  --underwater-world-oklch: oklch(0.563 0.033 180);
}

.element {
  color: var(--underwater-world);
  background-color: hsl(167 12% 43%);
  border-color: oklch(0.563 0.033 180);
}

Tailwind CSS v4

@theme {
  --color-underwater-world: #617c76;
  --color-underwater-world-50: #ecf8f6;
  --color-underwater-world-100: #ddece9;
  --color-underwater-world-200: #c6d9d5;
  --color-underwater-world-300: #a6bdb8;
  --color-underwater-world-400: #8aa59f;
  --color-underwater-world-500: #6f8e87;
  --color-underwater-world-600: #5e7872;
  --color-underwater-world-700: #4b605b;
  --color-underwater-world-800: #374642;
  --color-underwater-world-900: #25312e;
  --color-underwater-world-950: #141d1b;
}

SCSS

$underwater-world: #617c76;
$underwater-world-rgb: 97, 124, 118;
$underwater-world-light: mix(#fff, $underwater-world, 20%);
$underwater-world-dark: mix(#000, $underwater-world, 20%);

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