#E0EDF4

CSS

:root {
  --out-cold: #e0edf4;
  --out-cold-rgb: 224 237 244;
  --out-cold-oklch: oklch(0.938 0.017 230.9);
}

.element {
  color: var(--out-cold);
  background-color: hsl(201 48% 92%);
  border-color: oklch(0.938 0.017 230.9);
}

Tailwind CSS v4

@theme {
  --color-out-cold: #e0edf4;
  --color-out-cold-50: #f1f6f9;
  --color-out-cold-100: #e3e9ed;
  --color-out-cold-200: #ced6da;
  --color-out-cold-300: #afb9bf;
  --color-out-cold-400: #95a0a7;
  --color-out-cold-500: #7b888f;
  --color-out-cold-600: #697379;
  --color-out-cold-700: #545c61;
  --color-out-cold-800: #3d4447;
  --color-out-cold-900: #2a2f31;
  --color-out-cold-950: #171b1d;
}

SCSS

$out-cold: #e0edf4;
$out-cold-rgb: 224, 237, 244;
$out-cold-light: mix(#fff, $out-cold, 20%);
$out-cold-dark: mix(#000, $out-cold, 20%);

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