#D7F0F0

CSS

:root {
  --queen-of-waves: #d7f0f0;
  --queen-of-waves-rgb: 215 240 240;
  --queen-of-waves-oklch: oklch(0.937 0.026 196.7);
}

.element {
  color: var(--queen-of-waves);
  background-color: hsl(180 45% 89%);
  border-color: oklch(0.937 0.026 196.7);
}

Tailwind CSS v4

@theme {
  --color-queen-of-waves: #d7f0f0;
  --color-queen-of-waves-50: #edf8f8;
  --color-queen-of-waves-100: #deebeb;
  --color-queen-of-waves-200: #c8d8d8;
  --color-queen-of-waves-300: #a9bcbc;
  --color-queen-of-waves-400: #8da4a4;
  --color-queen-of-waves-500: #738c8c;
  --color-queen-of-waves-600: #617676;
  --color-queen-of-waves-700: #4e5f5f;
  --color-queen-of-waves-800: #384545;
  --color-queen-of-waves-900: #263030;
  --color-queen-of-waves-950: #151c1c;
}

SCSS

$queen-of-waves: #d7f0f0;
$queen-of-waves-rgb: 215, 240, 240;
$queen-of-waves-light: mix(#fff, $queen-of-waves, 20%);
$queen-of-waves-dark: mix(#000, $queen-of-waves, 20%);

.element {
  color: $queen-of-waves;
  box-shadow: 0 0 0 2px rgba($queen-of-waves, 0.35);
}