#623840

CSS

:root {
  --red-rumour: #623840;
  --red-rumour-rgb: 98 56 64;
  --red-rumour-oklch: oklch(0.395 0.061 7.9);
}

.element {
  color: var(--red-rumour);
  background-color: hsl(349 27% 30%);
  border-color: oklch(0.395 0.061 7.9);
}

Tailwind CSS v4

@theme {
  --color-red-rumour: #623840;
  --color-red-rumour-50: #ffeef1;
  --color-red-rumour-100: #fbe0e3;
  --color-red-rumour-200: #edcace;
  --color-red-rumour-300: #d4abb0;
  --color-red-rumour-400: #bf9098;
  --color-red-rumour-500: #aa767e;
  --color-red-rumour-600: #8f646b;
  --color-red-rumour-700: #735056;
  --color-red-rumour-800: #553a3f;
  --color-red-rumour-900: #3b272b;
  --color-red-rumour-950: #251619;
}

SCSS

$red-rumour: #623840;
$red-rumour-rgb: 98, 56, 64;
$red-rumour-light: mix(#fff, $red-rumour, 20%);
$red-rumour-dark: mix(#000, $red-rumour, 20%);

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