#3D817D

CSS

:root {
  --turquoise-tortoise: #3d817d;
  --turquoise-tortoise-rgb: 61 129 125;
  --turquoise-tortoise-oklch: oklch(0.558 0.069 190.2);
}

.element {
  color: var(--turquoise-tortoise);
  background-color: hsl(176 36% 37%);
  border-color: oklch(0.558 0.069 190.2);
}

Tailwind CSS v4

@theme {
  --color-turquoise-tortoise: #3d817d;
  --color-turquoise-tortoise-50: #e0fcfa;
  --color-turquoise-tortoise-100: #cff0ee;
  --color-turquoise-tortoise-200: #b3dedc;
  --color-turquoise-tortoise-300: #8ec3c1;
  --color-turquoise-tortoise-400: #6caca8;
  --color-turquoise-tortoise-500: #489590;
  --color-turquoise-tortoise-600: #3e7e7a;
  --color-turquoise-tortoise-700: #326562;
  --color-turquoise-tortoise-800: #234a47;
  --color-turquoise-tortoise-900: #173331;
  --color-turquoise-tortoise-950: #081f1d;
}

SCSS

$turquoise-tortoise: #3d817d;
$turquoise-tortoise-rgb: 61, 129, 125;
$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);
}