#008B8D

CSS

:root {
  --dark-cyan: #008b8d;
  --dark-cyan-rgb: 0 139 141;
  --dark-cyan-oklch: oklch(0.577 0.098 196.6);
}

.element {
  color: var(--dark-cyan);
  background-color: hsl(181 100% 28%);
  border-color: oklch(0.577 0.098 196.6);
}

Tailwind CSS v4

@theme {
  --color-dark-cyan: #008b8d;
  --color-dark-cyan-50: #d6feff;
  --color-dark-cyan-100: #c2f3f4;
  --color-dark-cyan-200: #a2e2e4;
  --color-dark-cyan-300: #77c7ca;
  --color-dark-cyan-400: #4bb0b2;
  --color-dark-cyan-500: #009a9c;
  --color-dark-cyan-600: #018284;
  --color-dark-cyan-700: #06686a;
  --color-dark-cyan-800: #034d4d;
  --color-dark-cyan-900: #033535;
  --color-dark-cyan-950: #002020;
}

SCSS

$dark-cyan: #008b8d;
$dark-cyan-rgb: 0, 139, 141;
$dark-cyan-light: mix(#fff, $dark-cyan, 20%);
$dark-cyan-dark: mix(#000, $dark-cyan, 20%);

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