#6E6C67

CSS

:root {
  --volcanic-rock: #6e6c67;
  --volcanic-rock-rgb: 110 108 103;
  --volcanic-rock-oklch: oklch(0.531 0.008 88.7);
}

.element {
  color: var(--volcanic-rock);
  background-color: hsl(43 3% 42%);
  border-color: oklch(0.531 0.008 88.7);
}

Tailwind CSS v4

@theme {
  --color-volcanic-rock: #6e6c67;
  --color-volcanic-rock-50: #f6f5f2;
  --color-volcanic-rock-100: #e9e8e5;
  --color-volcanic-rock-200: #d5d4d0;
  --color-volcanic-rock-300: #b9b7b3;
  --color-volcanic-rock-400: #a09e99;
  --color-volcanic-rock-500: #888680;
  --color-volcanic-rock-600: #73716d;
  --color-volcanic-rock-700: #5c5b57;
  --color-volcanic-rock-800: #43423f;
  --color-volcanic-rock-900: #2f2e2c;
  --color-volcanic-rock-950: #1b1a19;
}

SCSS

$volcanic-rock: #6e6c67;
$volcanic-rock-rgb: 110, 108, 103;
$volcanic-rock-light: mix(#fff, $volcanic-rock, 20%);
$volcanic-rock-dark: mix(#000, $volcanic-rock, 20%);

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