#4E7D78

CSS

:root {
  --turquoise-tortoise: #4e7d78;
  --turquoise-tortoise-rgb: 78 125 120;
  --turquoise-tortoise-oklch: oklch(0.554 0.052 187.3);
}

.element {
  color: var(--turquoise-tortoise);
  background-color: hsl(174 23% 40%);
  border-color: oklch(0.554 0.052 187.3);
}

Tailwind CSS v4

@theme {
  --color-turquoise-tortoise: #4e7d78;
  --color-turquoise-tortoise-50: #e5faf8;
  --color-turquoise-tortoise-100: #d5eeeb;
  --color-turquoise-tortoise-200: #bcdcd9;
  --color-turquoise-tortoise-300: #9ac0bd;
  --color-turquoise-tortoise-400: #7ba9a4;
  --color-turquoise-tortoise-500: #5d928c;
  --color-turquoise-tortoise-600: #4f7b76;
  --color-turquoise-tortoise-700: #3f635f;
  --color-turquoise-tortoise-800: #2d4845;
  --color-turquoise-tortoise-900: #1e3230;
  --color-turquoise-tortoise-950: #0e1e1c;
}

SCSS

$turquoise-tortoise: #4e7d78;
$turquoise-tortoise-rgb: 78, 125, 120;
$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);
}