#C45152

CSS

:root {
  --autumn-fire: #c45152;
  --autumn-fire-rgb: 196 81 82;
  --autumn-fire-oklch: oklch(0.585 0.148 22.3);
}

.element {
  color: var(--autumn-fire);
  background-color: hsl(359 49% 54%);
  border-color: oklch(0.585 0.148 22.3);
}

Tailwind CSS v4

@theme {
  --color-autumn-fire: #c45152;
  --color-autumn-fire-50: #ffe6e0;
  --color-autumn-fire-100: #ffd5d0;
  --color-autumn-fire-200: #ffbcb5;
  --color-autumn-fire-300: #fa9892;
  --color-autumn-fire-400: #e97876;
  --color-autumn-fire-500: #d65657;
  --color-autumn-fire-600: #b5494a;
  --color-autumn-fire-700: #923b3b;
  --color-autumn-fire-800: #6c292c;
  --color-autumn-fire-900: #4c1c1e;
  --color-autumn-fire-950: #320b0e;
}

SCSS

$autumn-fire: #c45152;
$autumn-fire-rgb: 196, 81, 82;
$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);
}