#00C9ED

CSS

:root {
  --caribbean-blue: #00c9ed;
  --caribbean-blue-rgb: 0 201 237;
  --caribbean-blue-oklch: oklch(0.771 0.138 216.9);
}

.element {
  color: var(--caribbean-blue);
  background-color: hsl(189 100% 46%);
  border-color: oklch(0.771 0.138 216.9);
}

Tailwind CSS v4

@theme {
  --color-caribbean-blue: #00c9ed;
  --color-caribbean-blue-50: #caffff;
  --color-caribbean-blue-100: #b4f4ff;
  --color-caribbean-blue-200: #8ee3fc;
  --color-caribbean-blue-300: #58c8e7;
  --color-caribbean-blue-400: #00b1d3;
  --color-caribbean-blue-500: #009ac1;
  --color-caribbean-blue-600: #0082a3;
  --color-caribbean-blue-700: #006882;
  --color-caribbean-blue-800: #004d60;
  --color-caribbean-blue-900: #003643;
  --color-caribbean-blue-950: #00212b;
}

SCSS

$caribbean-blue: #00c9ed;
$caribbean-blue-rgb: 0, 201, 237;
$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);
}