#B36121

CSS

:root {
  --polished-copper: #b36121;
  --polished-copper-rgb: 179 97 33;
  --polished-copper-oklch: oklch(0.578 0.129 53.8);
}

.element {
  color: var(--polished-copper);
  background-color: hsl(26 69% 42%);
  border-color: oklch(0.578 0.129 53.8);
}

Tailwind CSS v4

@theme {
  --color-polished-copper: #b36121;
  --color-polished-copper-50: #ffecd2;
  --color-polished-copper-100: #ffdebf;
  --color-polished-copper-200: #ffc69f;
  --color-polished-copper-300: #eba675;
  --color-polished-copper-400: #d98850;
  --color-polished-copper-500: #c66a21;
  --color-polished-copper-600: #a75a1e;
  --color-polished-copper-700: #864818;
  --color-polished-copper-800: #643311;
  --color-polished-copper-900: #47230b;
  --color-polished-copper-950: #2e1201;
}

SCSS

$polished-copper: #b36121;
$polished-copper-rgb: 179, 97, 33;
$polished-copper-light: mix(#fff, $polished-copper, 20%);
$polished-copper-dark: mix(#000, $polished-copper, 20%);

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