#75654F

CSS

:root {
  --heavy-brown: #75654f;
  --heavy-brown-rgb: 117 101 79;
  --heavy-brown-oklch: oklch(0.516 0.039 75.5);
}

.element {
  color: var(--heavy-brown);
  background-color: hsl(35 19% 38%);
  border-color: oklch(0.516 0.039 75.5);
}

Tailwind CSS v4

@theme {
  --color-heavy-brown: #75654f;
  --color-heavy-brown-50: #fbf4e9;
  --color-heavy-brown-100: #efe7da;
  --color-heavy-brown-200: #ded3c2;
  --color-heavy-brown-300: #c3b5a2;
  --color-heavy-brown-400: #ac9c85;
  --color-heavy-brown-500: #95836a;
  --color-heavy-brown-600: #7e6f5a;
  --color-heavy-brown-700: #655948;
  --color-heavy-brown-800: #4b4134;
  --color-heavy-brown-900: #342c23;
  --color-heavy-brown-950: #1f1a12;
}

SCSS

$heavy-brown: #75654f;
$heavy-brown-rgb: 117, 101, 79;
$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);
}