#DD3800

CSS

:root {
  --flame-of-prometheus: #dd3800;
  --flame-of-prometheus-rgb: 221 56 0;
  --flame-of-prometheus-oklch: oklch(0.59 0.208 34.9);
}

.element {
  color: var(--flame-of-prometheus);
  background-color: hsl(15 100% 43%);
  border-color: oklch(0.59 0.208 34.9);
}

Tailwind CSS v4

@theme {
  --color-flame-of-prometheus: #dd3800;
  --color-flame-of-prometheus-50: #ffe1cb;
  --color-flame-of-prometheus-100: #ffd0b7;
  --color-flame-of-prometheus-200: #ffb494;
  --color-flame-of-prometheus-300: #ff8c67;
  --color-flame-of-prometheus-400: #ff653f;
  --color-flame-of-prometheus-500: #f03400;
  --color-flame-of-prometheus-600: #cb2f00;
  --color-flame-of-prometheus-700: #a32600;
  --color-flame-of-prometheus-800: #7a1905;
  --color-flame-of-prometheus-900: #561004;
  --color-flame-of-prometheus-950: #3a0200;
}

SCSS

$flame-of-prometheus: #dd3800;
$flame-of-prometheus-rgb: 221, 56, 0;
$flame-of-prometheus-light: mix(#fff, $flame-of-prometheus, 20%);
$flame-of-prometheus-dark: mix(#000, $flame-of-prometheus, 20%);

.element {
  color: $flame-of-prometheus;
  box-shadow: 0 0 0 2px rgba($flame-of-prometheus, 0.35);
}