#8C5533

CSS

:root {
  --hello-fall: #8c5533;
  --hello-fall-rgb: 140 85 51;
  --hello-fall-oklch: oklch(0.505 0.088 51.3);
}

.element {
  color: var(--hello-fall);
  background-color: hsl(23 47% 37%);
  border-color: oklch(0.505 0.088 51.3);
}

Tailwind CSS v4

@theme {
  --color-hello-fall: #8c5533;
  --color-hello-fall-50: #ffefde;
  --color-hello-fall-100: #ffe1cd;
  --color-hello-fall-200: #f3cbb2;
  --color-hello-fall-300: #dcac8e;
  --color-hello-fall-400: #c9906e;
  --color-hello-fall-500: #b4754e;
  --color-hello-fall-600: #986343;
  --color-hello-fall-700: #7a4f35;
  --color-hello-fall-800: #5b3926;
  --color-hello-fall-900: #402719;
  --color-hello-fall-950: #28150a;
}

SCSS

$hello-fall: #8c5533;
$hello-fall-rgb: 140, 85, 51;
$hello-fall-light: mix(#fff, $hello-fall, 20%);
$hello-fall-dark: mix(#000, $hello-fall, 20%);

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