#45807B

CSS

:root {
  --turquoise-tortoise: #45807b;
  --turquoise-tortoise-rgb: 69 128 123;
  --turquoise-tortoise-oklch: oklch(0.558 0.062 188.4);
}

.element {
  color: var(--turquoise-tortoise);
  background-color: hsl(175 30% 39%);
  border-color: oklch(0.558 0.062 188.4);
}

Tailwind CSS v4

@theme {
  --color-turquoise-tortoise: #45807b;
  --color-turquoise-tortoise-50: #e2fbf9;
  --color-turquoise-tortoise-100: #d1efed;
  --color-turquoise-tortoise-200: #b7ddda;
  --color-turquoise-tortoise-300: #93c2bf;
  --color-turquoise-tortoise-400: #73aba5;
  --color-turquoise-tortoise-500: #51948e;
  --color-turquoise-tortoise-600: #467d78;
  --color-turquoise-tortoise-700: #376460;
  --color-turquoise-tortoise-800: #274a46;
  --color-turquoise-tortoise-900: #1a3330;
  --color-turquoise-tortoise-950: #0a1f1c;
}

SCSS

$turquoise-tortoise: #45807b;
$turquoise-tortoise-rgb: 69, 128, 123;
$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);
}