#667876

CSS

:root {
  --blue-blood: #667876;
  --blue-blood-rgb: 102 120 118;
  --blue-blood-oklch: oklch(0.557 0.021 188.4);
}

.element {
  color: var(--blue-blood);
  background-color: hsl(173 8% 44%);
  border-color: oklch(0.557 0.021 188.4);
}

Tailwind CSS v4

@theme {
  --color-blue-blood: #667876;
  --color-blue-blood-50: #eff7f6;
  --color-blue-blood-100: #e0eae9;
  --color-blue-blood-200: #cad7d6;
  --color-blue-blood-300: #acbbba;
  --color-blue-blood-400: #91a3a1;
  --color-blue-blood-500: #778b89;
  --color-blue-blood-600: #657674;
  --color-blue-blood-700: #505e5d;
  --color-blue-blood-800: #3a4543;
  --color-blue-blood-900: #28302f;
  --color-blue-blood-950: #161c1b;
}

SCSS

$blue-blood: #667876;
$blue-blood-rgb: 102, 120, 118;
$blue-blood-light: mix(#fff, $blue-blood, 20%);
$blue-blood-dark: mix(#000, $blue-blood, 20%);

.element {
  color: $blue-blood;
  box-shadow: 0 0 0 2px rgba($blue-blood, 0.35);
}