#CE2B31

CSS

:root {
  --persian-red: #ce2b31;
  --persian-red-rgb: 206 43 49;
  --persian-red-oklch: oklch(0.556 0.198 25);
}

.element {
  color: var(--persian-red);
  background-color: hsl(358 65% 49%);
  border-color: oklch(0.556 0.198 25);
}

Tailwind CSS v4

@theme {
  --color-persian-red: #ce2b31;
  --color-persian-red-50: #ffe0d7;
  --color-persian-red-100: #ffcfc4;
  --color-persian-red-200: #ffb2a6;
  --color-persian-red-300: #ff8b7f;
  --color-persian-red-400: #fe6560;
  --color-persian-red-500: #ed363b;
  --color-persian-red-600: #c83033;
  --color-persian-red-700: #a12729;
  --color-persian-red-800: #781a1f;
  --color-persian-red-900: #551114;
  --color-persian-red-950: #390206;
}

SCSS

$persian-red: #ce2b31;
$persian-red-rgb: 206, 43, 49;
$persian-red-light: mix(#fff, $persian-red, 20%);
$persian-red-dark: mix(#000, $persian-red, 20%);

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