#776969

CSS

:root {
  --acoustic-brown: #776969;
  --acoustic-brown-rgb: 119 105 105;
  --acoustic-brown-oklch: oklch(0.534 0.018 17.7);
}

.element {
  color: var(--acoustic-brown);
  background-color: hsl(0 6% 44%);
  border-color: oklch(0.534 0.018 17.7);
}

Tailwind CSS v4

@theme {
  --color-acoustic-brown: #776969;
  --color-acoustic-brown-50: #faf3f3;
  --color-acoustic-brown-100: #eee6e5;
  --color-acoustic-brown-200: #dcd1d1;
  --color-acoustic-brown-300: #c0b4b4;
  --color-acoustic-brown-400: #a99a9a;
  --color-acoustic-brown-500: #928282;
  --color-acoustic-brown-600: #7b6e6e;
  --color-acoustic-brown-700: #635858;
  --color-acoustic-brown-800: #484040;
  --color-acoustic-brown-900: #322c2c;
  --color-acoustic-brown-950: #1e1919;
}

SCSS

$acoustic-brown: #776969;
$acoustic-brown-rgb: 119, 105, 105;
$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);
}