#6D5D43

CSS

:root {
  --heavy-brown: #6d5d43;
  --heavy-brown-rgb: 109 93 67;
  --heavy-brown-oklch: oklch(0.487 0.044 79.5);
}

.element {
  color: var(--heavy-brown);
  background-color: hsl(37 24% 35%);
  border-color: oklch(0.487 0.044 79.5);
}

Tailwind CSS v4

@theme {
  --color-heavy-brown: #6d5d43;
  --color-heavy-brown-50: #fcf4e7;
  --color-heavy-brown-100: #efe7d8;
  --color-heavy-brown-200: #ded3c0;
  --color-heavy-brown-300: #c3b69f;
  --color-heavy-brown-400: #ac9c82;
  --color-heavy-brown-500: #968365;
  --color-heavy-brown-600: #7f6f56;
  --color-heavy-brown-700: #655944;
  --color-heavy-brown-800: #4b4131;
  --color-heavy-brown-900: #342d21;
  --color-heavy-brown-950: #1f1a11;
}

SCSS

$heavy-brown: #6d5d43;
$heavy-brown-rgb: 109, 93, 67;
$heavy-brown-light: mix(#fff, $heavy-brown, 20%);
$heavy-brown-dark: mix(#000, $heavy-brown, 20%);

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