#C73732

CSS

:root {
  --smouldering-red: #c73732;
  --smouldering-red-rgb: 199 55 50;
  --smouldering-red-oklch: oklch(0.554 0.182 27);
}

.element {
  color: var(--smouldering-red);
  background-color: hsl(2 60% 49%);
  border-color: oklch(0.554 0.182 27);
}

Tailwind CSS v4

@theme {
  --color-smouldering-red: #c73732;
  --color-smouldering-red-50: #ffe2d8;
  --color-smouldering-red-100: #ffd2c5;
  --color-smouldering-red-200: #ffb6a7;
  --color-smouldering-red-300: #ff9180;
  --color-smouldering-red-400: #f76c61;
  --color-smouldering-red-500: #e6443d;
  --color-smouldering-red-600: #c23b35;
  --color-smouldering-red-700: #9c2f2a;
  --color-smouldering-red-800: #752020;
  --color-smouldering-red-900: #521515;
  --color-smouldering-red-950: #370507;
}

SCSS

$smouldering-red: #c73732;
$smouldering-red-rgb: 199, 55, 50;
$smouldering-red-light: mix(#fff, $smouldering-red, 20%);
$smouldering-red-dark: mix(#000, $smouldering-red, 20%);

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