#BD5350

CSS

:root {
  --autumn-fire: #bd5350;
  --autumn-fire-rgb: 189 83 80;
  --autumn-fire-oklch: oklch(0.577 0.138 24);
}

.element {
  color: var(--autumn-fire);
  background-color: hsl(2 45% 53%);
  border-color: oklch(0.577 0.138 24);
}

Tailwind CSS v4

@theme {
  --color-autumn-fire: #bd5350;
  --color-autumn-fire-50: #ffe7e1;
  --color-autumn-fire-100: #ffd7d0;
  --color-autumn-fire-200: #ffbeb6;
  --color-autumn-fire-300: #f69b92;
  --color-autumn-fire-400: #e47b76;
  --color-autumn-fire-500: #d25b58;
  --color-autumn-fire-600: #b14e4b;
  --color-autumn-fire-700: #8e3e3b;
  --color-autumn-fire-800: #6a2c2c;
  --color-autumn-fire-900: #4b1e1e;
  --color-autumn-fire-950: #310d0e;
}

SCSS

$autumn-fire: #bd5350;
$autumn-fire-rgb: 189, 83, 80;
$autumn-fire-light: mix(#fff, $autumn-fire, 20%);
$autumn-fire-dark: mix(#000, $autumn-fire, 20%);

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