#A8641F

CSS

:root {
  --light-brown: #a8641f;
  --light-brown-rgb: 168 100 31;
  --light-brown-oklch: oklch(0.568 0.118 60.8);
}

.element {
  color: var(--light-brown);
  background-color: hsl(30 69% 39%);
  border-color: oklch(0.568 0.118 60.8);
}

Tailwind CSS v4

@theme {
  --color-light-brown: #a8641f;
  --color-light-brown-50: #ffefd3;
  --color-light-brown-100: #ffe0c0;
  --color-light-brown-200: #f9caa0;
  --color-light-brown-300: #e3aa77;
  --color-light-brown-400: #d18d51;
  --color-light-brown-500: #bd7123;
  --color-light-brown-600: #a06020;
  --color-light-brown-700: #804d1a;
  --color-light-brown-800: #603712;
  --color-light-brown-900: #43260b;
  --color-light-brown-950: #2b1401;
}

SCSS

$light-brown: #a8641f;
$light-brown-rgb: 168, 100, 31;
$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);
}