#00819D

CSS

:root {
  --ahoy-blue: #00819d;
  --ahoy-blue-rgb: 0 129 157;
  --ahoy-blue-oklch: oklch(0.558 0.102 220.1);
}

.element {
  color: var(--ahoy-blue);
  background-color: hsl(191 100% 31%);
  border-color: oklch(0.558 0.102 220.1);
}

Tailwind CSS v4

@theme {
  --color-ahoy-blue: #00819d;
  --color-ahoy-blue-50: #d7fcff;
  --color-ahoy-blue-100: #c4f0ff;
  --color-ahoy-blue-200: #a4dff4;
  --color-ahoy-blue-300: #7ac4dd;
  --color-ahoy-blue-400: #4facc8;
  --color-ahoy-blue-500: #0795b5;
  --color-ahoy-blue-600: #117e98;
  --color-ahoy-blue-700: #0f657a;
  --color-ahoy-blue-800: #054a5a;
  --color-ahoy-blue-900: #05343f;
  --color-ahoy-blue-950: #001f28;
}

SCSS

$ahoy-blue: #00819d;
$ahoy-blue-rgb: 0, 129, 157;
$ahoy-blue-light: mix(#fff, $ahoy-blue, 20%);
$ahoy-blue-dark: mix(#000, $ahoy-blue, 20%);

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