#766A65

CSS

:root {
  --acoustic-brown: #766a65;
  --acoustic-brown-rgb: 118 106 101;
  --acoustic-brown-oklch: oklch(0.534 0.017 44);
}

.element {
  color: var(--acoustic-brown);
  background-color: hsl(18 8% 43%);
  border-color: oklch(0.534 0.017 44);
}

Tailwind CSS v4

@theme {
  --color-acoustic-brown: #766a65;
  --color-acoustic-brown-50: #faf4f1;
  --color-acoustic-brown-100: #ede6e3;
  --color-acoustic-brown-200: #dbd2ce;
  --color-acoustic-brown-300: #bfb5b0;
  --color-acoustic-brown-400: #a89b96;
  --color-acoustic-brown-500: #91837d;
  --color-acoustic-brown-600: #7a6f6a;
  --color-acoustic-brown-700: #625955;
  --color-acoustic-brown-800: #48413e;
  --color-acoustic-brown-900: #322c2a;
  --color-acoustic-brown-950: #1e1a18;
}

SCSS

$acoustic-brown: #766a65;
$acoustic-brown-rgb: 118, 106, 101;
$acoustic-brown-light: mix(#fff, $acoustic-brown, 20%);
$acoustic-brown-dark: mix(#000, $acoustic-brown, 20%);

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