#C73631

CSS

:root {
  --smouldering-red: #c73631;
  --smouldering-red-rgb: 199 54 49;
  --smouldering-red-oklch: oklch(0.553 0.183 27.1);
}

.element {
  color: var(--smouldering-red);
  background-color: hsl(2 60% 49%);
  border-color: oklch(0.553 0.183 27.1);
}

Tailwind CSS v4

@theme {
  --color-smouldering-red: #c73631;
  --color-smouldering-red-50: #ffe2d7;
  --color-smouldering-red-100: #ffd1c5;
  --color-smouldering-red-200: #ffb6a7;
  --color-smouldering-red-300: #ff9080;
  --color-smouldering-red-400: #f86c61;
  --color-smouldering-red-500: #e6433d;
  --color-smouldering-red-600: #c23a34;
  --color-smouldering-red-700: #9c2f29;
  --color-smouldering-red-800: #75201f;
  --color-smouldering-red-900: #531515;
  --color-smouldering-red-950: #370506;
}

SCSS

$smouldering-red: #c73631;
$smouldering-red-rgb: 199, 54, 49;
$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);
}