Hūi Sè Grey

CSS

:root {
  --hui-se-grey: #c1c6d3;
  --hui-se-grey-rgb: 193 198 211;
  --hui-se-grey-oklch: oklch(0.827 0.019 269.1);
}

.element {
  color: var(--hui-se-grey);
  background-color: hsl(223 17% 79%);
  border-color: oklch(0.827 0.019 269.1);
}

Tailwind CSS v4

@theme {
  --color-hui-se-grey: #c1c6d3;
  --color-hui-se-grey-50: #f3f5fb;
  --color-hui-se-grey-100: #e5e8ee;
  --color-hui-se-grey-200: #d1d4dd;
  --color-hui-se-grey-300: #b4b7c1;
  --color-hui-se-grey-400: #9a9eaa;
  --color-hui-se-grey-500: #818693;
  --color-hui-se-grey-600: #6d717c;
  --color-hui-se-grey-700: #575b64;
  --color-hui-se-grey-800: #3f4249;
  --color-hui-se-grey-900: #2c2e33;
  --color-hui-se-grey-950: #191b1e;
}

SCSS

$hui-se-grey: #c1c6d3;
$hui-se-grey-rgb: 193, 198, 211;
$hui-se-grey-light: mix(#fff, $hui-se-grey, 20%);
$hui-se-grey-dark: mix(#000, $hui-se-grey, 20%);

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