#00BBD4

CSS

:root {
  --caribbean-blue: #00bbd4;
  --caribbean-blue-rgb: 0 187 212;
  --caribbean-blue-oklch: oklch(0.727 0.126 211.5);
}

.element {
  color: var(--caribbean-blue);
  background-color: hsl(187 100% 42%);
  border-color: oklch(0.727 0.126 211.5);
}

Tailwind CSS v4

@theme {
  --color-caribbean-blue: #00bbd4;
  --color-caribbean-blue-50: #cdffff;
  --color-caribbean-blue-100: #b8f4ff;
  --color-caribbean-blue-200: #93e3f5;
  --color-caribbean-blue-300: #60c8de;
  --color-caribbean-blue-400: #0eb2c9;
  --color-caribbean-blue-500: #009bb6;
  --color-caribbean-blue-600: #00839a;
  --color-caribbean-blue-700: #00697b;
  --color-caribbean-blue-800: #004d5a;
  --color-caribbean-blue-900: #00363f;
  --color-caribbean-blue-950: #002128;
}

SCSS

$caribbean-blue: #00bbd4;
$caribbean-blue-rgb: 0, 187, 212;
$caribbean-blue-light: mix(#fff, $caribbean-blue, 20%);
$caribbean-blue-dark: mix(#000, $caribbean-blue, 20%);

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