#81684D

CSS

:root {
  --pastel-brown: #81684d;
  --pastel-brown-rgb: 129 104 77;
  --pastel-brown-oklch: oklch(0.535 0.051 68.6);
}

.element {
  color: var(--pastel-brown);
  background-color: hsl(31 25% 40%);
  border-color: oklch(0.535 0.051 68.6);
}

Tailwind CSS v4

@theme {
  --color-pastel-brown: #81684d;
  --color-pastel-brown-50: #fff3e6;
  --color-pastel-brown-100: #f3e5d6;
  --color-pastel-brown-200: #e3d1bd;
  --color-pastel-brown-300: #c9b49c;
  --color-pastel-brown-400: #b3997e;
  --color-pastel-brown-500: #9d8062;
  --color-pastel-brown-600: #856d53;
  --color-pastel-brown-700: #6a5742;
  --color-pastel-brown-800: #4f3f30;
  --color-pastel-brown-900: #372b20;
  --color-pastel-brown-950: #221910;
}

SCSS

$pastel-brown: #81684d;
$pastel-brown-rgb: 129, 104, 77;
$pastel-brown-light: mix(#fff, $pastel-brown, 20%);
$pastel-brown-dark: mix(#000, $pastel-brown, 20%);

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