#DDECE9

CSS

:root {
  --second-wind: #ddece9;
  --second-wind-rgb: 221 236 233;
  --second-wind-oklch: oklch(0.931 0.016 182.7);
}

.element {
  color: var(--second-wind);
  background-color: hsl(168 28% 90%);
  border-color: oklch(0.931 0.016 182.7);
}

Tailwind CSS v4

@theme {
  --color-second-wind: #ddece9;
  --color-second-wind-50: #f0f7f6;
  --color-second-wind-100: #e2eae8;
  --color-second-wind-200: #cdd7d5;
  --color-second-wind-300: #afbab8;
  --color-second-wind-400: #94a29f;
  --color-second-wind-500: #7b8a87;
  --color-second-wind-600: #687572;
  --color-second-wind-700: #535d5b;
  --color-second-wind-800: #3c4443;
  --color-second-wind-900: #2a2f2e;
  --color-second-wind-950: #171c1b;
}

SCSS

$second-wind: #ddece9;
$second-wind-rgb: 221, 236, 233;
$second-wind-light: mix(#fff, $second-wind, 20%);
$second-wind-dark: mix(#000, $second-wind, 20%);

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