#AA978F

CSS

:root {
  --cortex: #aa978f;
  --cortex-rgb: 170 151 143;
  --cortex-oklch: oklch(0.691 0.025 44.2);
}

.element {
  color: var(--cortex);
  background-color: hsl(18 14% 61%);
  border-color: oklch(0.691 0.025 44.2);
}

Tailwind CSS v4

@theme {
  --color-cortex: #aa978f;
  --color-cortex-50: #fcf3ef;
  --color-cortex-100: #f0e5e1;
  --color-cortex-200: #ded1cb;
  --color-cortex-300: #c3b4ad;
  --color-cortex-400: #ac9a92;
  --color-cortex-500: #958179;
  --color-cortex-600: #7e6d66;
  --color-cortex-700: #655752;
  --color-cortex-800: #4a403c;
  --color-cortex-900: #342c29;
  --color-cortex-950: #1f1917;
}

SCSS

$cortex: #aa978f;
$cortex-rgb: 170, 151, 143;
$cortex-light: mix(#fff, $cortex, 20%);
$cortex-dark: mix(#000, $cortex, 20%);

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