#AB3600

CSS

:root {
  --rust: #ab3600;
  --rust-rgb: 171 54 0;
  --rust-oklch: oklch(0.501 0.161 38.8);
}

.element {
  color: var(--rust);
  background-color: hsl(19 100% 34%);
  border-color: oklch(0.501 0.161 38.8);
}

Tailwind CSS v4

@theme {
  --color-rust: #ab3600;
  --color-rust-50: #ffe7d2;
  --color-rust-100: #ffd7bf;
  --color-rust-200: #ffbd9f;
  --color-rust-300: #fd9a76;
  --color-rust-400: #ed7852;
  --color-rust-500: #db5625;
  --color-rust-600: #b94922;
  --color-rust-700: #943b1b;
  --color-rust-800: #6f2914;
  --color-rust-900: #4e1c0d;
  --color-rust-950: #340b02;
}

SCSS

$rust: #ab3600;
$rust-rgb: 171, 54, 0;
$rust-light: mix(#fff, $rust, 20%);
$rust-dark: mix(#000, $rust, 20%);

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