#B56021

CSS

:root {
  --polished-copper: #b56021;
  --polished-copper-rgb: 181 96 33;
  --polished-copper-oklch: oklch(0.579 0.132 52.4);
}

.element {
  color: var(--polished-copper);
  background-color: hsl(26 69% 42%);
  border-color: oklch(0.579 0.132 52.4);
}

Tailwind CSS v4

@theme {
  --color-polished-copper: #b56021;
  --color-polished-copper-50: #ffecd2;
  --color-polished-copper-100: #ffddbf;
  --color-polished-copper-200: #ffc69f;
  --color-polished-copper-300: #eca575;
  --color-polished-copper-400: #db8750;
  --color-polished-copper-500: #c86920;
  --color-polished-copper-600: #a9591e;
  --color-polished-copper-700: #884718;
  --color-polished-copper-800: #653311;
  --color-polished-copper-900: #47230b;
  --color-polished-copper-950: #2e1101;
}

SCSS

$polished-copper: #b56021;
$polished-copper-rgb: 181, 96, 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);
}