#43756F

CSS

:root {
  --turquoise-tortoise: #43756f;
  --turquoise-tortoise-rgb: 67 117 111;
  --turquoise-tortoise-oklch: oklch(0.525 0.055 185.9);
}

.element {
  color: var(--turquoise-tortoise);
  background-color: hsl(173 27% 36%);
  border-color: oklch(0.525 0.055 185.9);
}

Tailwind CSS v4

@theme {
  --color-turquoise-tortoise: #43756f;
  --color-turquoise-tortoise-50: #e4fbf8;
  --color-turquoise-tortoise-100: #d4eeeb;
  --color-turquoise-tortoise-200: #bbdcd8;
  --color-turquoise-tortoise-300: #98c1bc;
  --color-turquoise-tortoise-400: #79a9a3;
  --color-turquoise-tortoise-500: #5a928b;
  --color-turquoise-tortoise-600: #4d7c76;
  --color-turquoise-tortoise-700: #3d635e;
  --color-turquoise-tortoise-800: #2c4944;
  --color-turquoise-tortoise-900: #1d322f;
  --color-turquoise-tortoise-950: #0d1e1c;
}

SCSS

$turquoise-tortoise: #43756f;
$turquoise-tortoise-rgb: 67, 117, 111;
$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);
}