#E3F1FA

CSS

:root {
  --out-cold: #e3f1fa;
  --out-cold-rgb: 227 241 250;
  --out-cold-oklch: oklch(0.95 0.019 235.7);
}

.element {
  color: var(--out-cold);
  background-color: hsl(203 70% 94%);
  border-color: oklch(0.95 0.019 235.7);
}

Tailwind CSS v4

@theme {
  --color-out-cold: #e3f1fa;
  --color-out-cold-50: #f0f6fa;
  --color-out-cold-100: #e2e9ee;
  --color-out-cold-200: #cdd6dc;
  --color-out-cold-300: #afb9c0;
  --color-out-cold-400: #94a0a8;
  --color-out-cold-500: #7b8891;
  --color-out-cold-600: #68737b;
  --color-out-cold-700: #535c62;
  --color-out-cold-800: #3c4448;
  --color-out-cold-900: #292f32;
  --color-out-cold-950: #171b1e;
}

SCSS

$out-cold: #e3f1fa;
$out-cold-rgb: 227, 241, 250;
$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);
}