#517F72

CSS

:root {
  --turquoise-tortoise: #517f72;
  --turquoise-tortoise-rgb: 81 127 114;
  --turquoise-tortoise-oklch: oklch(0.559 0.055 174.5);
}

.element {
  color: var(--turquoise-tortoise);
  background-color: hsl(163 22% 41%);
  border-color: oklch(0.559 0.055 174.5);
}

Tailwind CSS v4

@theme {
  --color-turquoise-tortoise: #517f72;
  --color-turquoise-tortoise-50: #e6fbf5;
  --color-turquoise-tortoise-100: #d6eee7;
  --color-turquoise-tortoise-200: #bddcd3;
  --color-turquoise-tortoise-300: #9bc1b6;
  --color-turquoise-tortoise-400: #7da99c;
  --color-turquoise-tortoise-500: #5e9284;
  --color-turquoise-tortoise-600: #507c6f;
  --color-turquoise-tortoise-700: #406359;
  --color-turquoise-tortoise-800: #2e4940;
  --color-turquoise-tortoise-900: #1f322c;
  --color-turquoise-tortoise-950: #0f1e19;
}

SCSS

$turquoise-tortoise: #517f72;
$turquoise-tortoise-rgb: 81, 127, 114;
$turquoise-tortoise-light: mix(#fff, $turquoise-tortoise, 20%);
$turquoise-tortoise-dark: mix(#000, $turquoise-tortoise, 20%);

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