#B34C36

CSS

:root {
  --crimson-boy: #b34c36;
  --crimson-boy-rgb: 179 76 54;
  --crimson-boy-oklch: oklch(0.547 0.139 33.6);
}

.element {
  color: var(--crimson-boy);
  background-color: hsl(11 54% 46%);
  border-color: oklch(0.547 0.139 33.6);
}

Tailwind CSS v4

@theme {
  --color-crimson-boy: #b34c36;
  --color-crimson-boy-50: #ffe8da;
  --color-crimson-boy-100: #ffd8c8;
  --color-crimson-boy-200: #ffc0ac;
  --color-crimson-boy-300: #f59d86;
  --color-crimson-boy-400: #e47d66;
  --color-crimson-boy-500: #d25d44;
  --color-crimson-boy-600: #b1503b;
  --color-crimson-boy-700: #8e3f2e;
  --color-crimson-boy-800: #6a2d22;
  --color-crimson-boy-900: #4b1e17;
  --color-crimson-boy-950: #310e08;
}

SCSS

$crimson-boy: #b34c36;
$crimson-boy-rgb: 179, 76, 54;
$crimson-boy-light: mix(#fff, $crimson-boy, 20%);
$crimson-boy-dark: mix(#000, $crimson-boy, 20%);

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