#6E7677

CSS

:root {
  --volcanic-ash: #6e7677;
  --volcanic-ash-rgb: 110 118 119;
  --volcanic-ash-oklch: oklch(0.559 0.01 205.8);
}

.element {
  color: var(--volcanic-ash);
  background-color: hsl(187 4% 45%);
  border-color: oklch(0.559 0.01 205.8);
}

Tailwind CSS v4

@theme {
  --color-volcanic-ash: #6e7677;
  --color-volcanic-ash-50: #f2f6f6;
  --color-volcanic-ash-100: #e4e9e9;
  --color-volcanic-ash-200: #d0d5d6;
  --color-volcanic-ash-300: #b2b9ba;
  --color-volcanic-ash-400: #98a0a1;
  --color-volcanic-ash-500: #7f8889;
  --color-volcanic-ash-600: #6c7374;
  --color-volcanic-ash-700: #565c5d;
  --color-volcanic-ash-800: #3f4344;
  --color-volcanic-ash-900: #2b2f2f;
  --color-volcanic-ash-950: #181b1b;
}

SCSS

$volcanic-ash: #6e7677;
$volcanic-ash-rgb: 110, 118, 119;
$volcanic-ash-light: mix(#fff, $volcanic-ash, 20%);
$volcanic-ash-dark: mix(#000, $volcanic-ash, 20%);

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