#D4DEEC

CSS

:root {
  --cold-shoulder: #d4deec;
  --cold-shoulder-rgb: 212 222 236;
  --cold-shoulder-oklch: oklch(0.897 0.022 256.7);
}

.element {
  color: var(--cold-shoulder);
  background-color: hsl(215 39% 88%);
  border-color: oklch(0.897 0.022 256.7);
}

Tailwind CSS v4

@theme {
  --color-cold-shoulder: #d4deec;
  --color-cold-shoulder-50: #f1f5fc;
  --color-cold-shoulder-100: #e3e8ef;
  --color-cold-shoulder-200: #cfd5de;
  --color-cold-shoulder-300: #b1b8c3;
  --color-cold-shoulder-400: #969fac;
  --color-cold-shoulder-500: #7d8795;
  --color-cold-shoulder-600: #6a727e;
  --color-cold-shoulder-700: #555b65;
  --color-cold-shoulder-800: #3d434a;
  --color-cold-shoulder-900: #2a2e33;
  --color-cold-shoulder-950: #181b1f;
}

SCSS

$cold-shoulder: #d4deec;
$cold-shoulder-rgb: 212, 222, 236;
$cold-shoulder-light: mix(#fff, $cold-shoulder, 20%);
$cold-shoulder-dark: mix(#000, $cold-shoulder, 20%);

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