#D6E4F3

CSS

:root {
  --cold-shoulder: #d6e4f3;
  --cold-shoulder-rgb: 214 228 243;
  --cold-shoulder-oklch: oklch(0.913 0.025 250);
}

.element {
  color: var(--cold-shoulder);
  background-color: hsl(211 55% 90%);
  border-color: oklch(0.913 0.025 250);
}

Tailwind CSS v4

@theme {
  --color-cold-shoulder: #d6e4f3;
  --color-cold-shoulder-50: #f0f6fc;
  --color-cold-shoulder-100: #e2e9f0;
  --color-cold-shoulder-200: #cdd5df;
  --color-cold-shoulder-300: #aeb9c4;
  --color-cold-shoulder-400: #93a0ad;
  --color-cold-shoulder-500: #7a8897;
  --color-cold-shoulder-600: #677380;
  --color-cold-shoulder-700: #525c66;
  --color-cold-shoulder-800: #3c434b;
  --color-cold-shoulder-900: #292e34;
  --color-cold-shoulder-950: #171b1f;
}

SCSS

$cold-shoulder: #d6e4f3;
$cold-shoulder-rgb: 214, 228, 243;
$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);
}