#856900

CSS

:root {
  --muddy-brown: #856900;
  --muddy-brown-rgb: 133 105 0;
  --muddy-brown-oklch: oklch(0.533 0.109 90.3);
}

.element {
  color: var(--muddy-brown);
  background-color: hsl(47 100% 26%);
  border-color: oklch(0.533 0.109 90.3);
}

Tailwind CSS v4

@theme {
  --color-muddy-brown: #856900;
  --color-muddy-brown-50: #fff5d3;
  --color-muddy-brown-100: #f5e8bf;
  --color-muddy-brown-200: #e5d49f;
  --color-muddy-brown-300: #cbb675;
  --color-muddy-brown-400: #b79c4d;
  --color-muddy-brown-500: #a28218;
  --color-muddy-brown-600: #896e19;
  --color-muddy-brown-700: #6e5814;
  --color-muddy-brown-800: #52400c;
  --color-muddy-brown-900: #392c07;
  --color-muddy-brown-950: #231900;
}

SCSS

$muddy-brown: #856900;
$muddy-brown-rgb: 133, 105, 0;
$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);
}