#AD6121

CSS

:root {
  --light-brown: #ad6121;
  --light-brown-rgb: 173 97 33;
  --light-brown-oklch: oklch(0.569 0.124 55.9);
}

.element {
  color: var(--light-brown);
  background-color: hsl(27 68% 40%);
  border-color: oklch(0.569 0.124 55.9);
}

Tailwind CSS v4

@theme {
  --color-light-brown: #ad6121;
  --color-light-brown-50: #ffedd3;
  --color-light-brown-100: #ffdfc0;
  --color-light-brown-200: #fdc8a0;
  --color-light-brown-300: #e7a877;
  --color-light-brown-400: #d68a52;
  --color-light-brown-500: #c36d24;
  --color-light-brown-600: #a45d21;
  --color-light-brown-700: #844a1b;
  --color-light-brown-800: #633513;
  --color-light-brown-900: #45240c;
  --color-light-brown-950: #2d1301;
}

SCSS

$light-brown: #ad6121;
$light-brown-rgb: 173, 97, 33;
$light-brown-light: mix(#fff, $light-brown, 20%);
$light-brown-dark: mix(#000, $light-brown, 20%);

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