#643100

CSS

:root {
  --brown: #643100;
  --brown-rgb: 100 49 0;
  --brown-oklch: oklch(0.373 0.092 55.9);
}

.element {
  color: var(--brown);
  background-color: hsl(29 100% 20%);
  border-color: oklch(0.373 0.092 55.9);
}

Tailwind CSS v4

@theme {
  --color-brown: #643100;
  --color-brown-50: #ffefdc;
  --color-brown-100: #ffe1cb;
  --color-brown-200: #f3cbae;
  --color-brown-300: #dcac89;
  --color-brown-400: #c89069;
  --color-brown-500: #b47547;
  --color-brown-600: #98633d;
  --color-brown-700: #7a4f30;
  --color-brown-800: #5b3923;
  --color-brown-900: #402717;
  --color-brown-950: #281508;
}

SCSS

$brown: #643100;
$brown-rgb: 100, 49, 0;
$brown-light: mix(#fff, $brown, 20%);
$brown-dark: mix(#000, $brown, 20%);

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