Red Sentinel

CSS

:root {
  --red-sentinel: #b9090f;
  --red-sentinel-rgb: 185 9 15;
  --red-sentinel-oklch: oklch(0.497 0.199 28);
}

.element {
  color: var(--red-sentinel);
  background-color: hsl(358 91% 38%);
  border-color: oklch(0.497 0.199 28);
}

Tailwind CSS v4

@theme {
  --color-red-sentinel: #b9090f;
  --color-red-sentinel-50: #ffe1d4;
  --color-red-sentinel-100: #ffcfc1;
  --color-red-sentinel-200: #ffb3a1;
  --color-red-sentinel-300: #ff8c79;
  --color-red-sentinel-400: #fe6558;
  --color-red-sentinel-500: #ed372f;
  --color-red-sentinel-600: #c8312a;
  --color-red-sentinel-700: #a12721;
  --color-red-sentinel-800: #791a1a;
  --color-red-sentinel-900: #551110;
  --color-red-sentinel-950: #390204;
}

SCSS

$red-sentinel: #b9090f;
$red-sentinel-rgb: 185, 9, 15;
$red-sentinel-light: mix(#fff, $red-sentinel, 20%);
$red-sentinel-dark: mix(#000, $red-sentinel, 20%);

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