#83690F

CSS

:root {
  --muddy-brown: #83690f;
  --muddy-brown-rgb: 131 105 15;
  --muddy-brown-oklch: oklch(0.532 0.104 90.7);
}

.element {
  color: var(--muddy-brown);
  background-color: hsl(47 79% 29%);
  border-color: oklch(0.532 0.104 90.7);
}

Tailwind CSS v4

@theme {
  --color-muddy-brown: #83690f;
  --color-muddy-brown-50: #fff5d4;
  --color-muddy-brown-100: #f4e8c1;
  --color-muddy-brown-200: #e4d4a2;
  --color-muddy-brown-300: #cab679;
  --color-muddy-brown-400: #b69c52;
  --color-muddy-brown-500: #a08324;
  --color-muddy-brown-600: #876f21;
  --color-muddy-brown-700: #6c591a;
  --color-muddy-brown-800: #514010;
  --color-muddy-brown-900: #382c0a;
  --color-muddy-brown-950: #231900;
}

SCSS

$muddy-brown: #83690f;
$muddy-brown-rgb: 131, 105, 15;
$muddy-brown-light: mix(#fff, $muddy-brown, 20%);
$muddy-brown-dark: mix(#000, $muddy-brown, 20%);

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