#40817F

CSS

:root {
  --turquoise-tortoise: #40817f;
  --turquoise-tortoise-rgb: 64 129 127;
  --turquoise-tortoise-oklch: oklch(0.56 0.067 192.8);
}

.element {
  color: var(--turquoise-tortoise);
  background-color: hsl(178 34% 38%);
  border-color: oklch(0.56 0.067 192.8);
}

Tailwind CSS v4

@theme {
  --color-turquoise-tortoise: #40817f;
  --color-turquoise-tortoise-50: #e0fcfb;
  --color-turquoise-tortoise-100: #cfefef;
  --color-turquoise-tortoise-200: #b4dedd;
  --color-turquoise-tortoise-300: #90c3c2;
  --color-turquoise-tortoise-400: #6eaba9;
  --color-turquoise-tortoise-500: #4b9492;
  --color-turquoise-tortoise-600: #417d7c;
  --color-turquoise-tortoise-700: #336463;
  --color-turquoise-tortoise-800: #244a48;
  --color-turquoise-tortoise-900: #183332;
  --color-turquoise-tortoise-950: #081f1e;
}

SCSS

$turquoise-tortoise: #40817f;
$turquoise-tortoise-rgb: 64, 129, 127;
$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);
}