#877404

CSS

:root {
  --muddy-brown: #877404;
  --muddy-brown-rgb: 135 116 4;
  --muddy-brown-oklch: oklch(0.56 0.114 97.6);
}

.element {
  color: var(--muddy-brown);
  background-color: hsl(51 94% 27%);
  border-color: oklch(0.56 0.114 97.6);
}

Tailwind CSS v4

@theme {
  --color-muddy-brown: #877404;
  --color-muddy-brown-50: #fdf7d1;
  --color-muddy-brown-100: #f1e9be;
  --color-muddy-brown-200: #e0d69d;
  --color-muddy-brown-300: #c5b973;
  --color-muddy-brown-400: #b19f49;
  --color-muddy-brown-500: #9b8609;
  --color-muddy-brown-600: #837110;
  --color-muddy-brown-700: #695b0e;
  --color-muddy-brown-800: #4e4206;
  --color-muddy-brown-900: #372d05;
  --color-muddy-brown-950: #221a00;
}

SCSS

$muddy-brown: #877404;
$muddy-brown-rgb: 135, 116, 4;
$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);
}