#B75F1B

CSS

:root {
  --polished-copper: #b75f1b;
  --polished-copper-rgb: 183 95 27;
  --polished-copper-oklch: oklch(0.58 0.136 52.5);
}

.element {
  color: var(--polished-copper);
  background-color: hsl(26 74% 41%);
  border-color: oklch(0.58 0.136 52.5);
}

Tailwind CSS v4

@theme {
  --color-polished-copper: #b75f1b;
  --color-polished-copper-50: #ffecd1;
  --color-polished-copper-100: #ffddbd;
  --color-polished-copper-200: #ffc59d;
  --color-polished-copper-300: #eea472;
  --color-polished-copper-400: #dd864c;
  --color-polished-copper-500: #ca6718;
  --color-polished-copper-600: #ab5818;
  --color-polished-copper-700: #894614;
  --color-polished-copper-800: #66320e;
  --color-polished-copper-900: #482209;
  --color-polished-copper-950: #2f1100;
}

SCSS

$polished-copper: #b75f1b;
$polished-copper-rgb: 183, 95, 27;
$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);
}