Boston Blue

CSS

:root {
  --boston-blue: #438eac;
  --boston-blue-rgb: 67 142 172;
  --boston-blue-oklch: oklch(0.611 0.087 227);
}

.element {
  color: var(--boston-blue);
  background-color: hsl(197 44% 47%);
  border-color: oklch(0.611 0.087 227);
}

Tailwind CSS v4

@theme {
  --color-boston-blue: #438eac;
  --color-boston-blue-50: #ddfbff;
  --color-boston-blue-100: #cbeeff;
  --color-boston-blue-200: #afdcf2;
  --color-boston-blue-300: #88c1db;
  --color-boston-blue-400: #63a9c6;
  --color-boston-blue-500: #3c91b3;
  --color-boston-blue-600: #347b97;
  --color-boston-blue-700: #296379;
  --color-boston-blue-800: #1b4959;
  --color-boston-blue-900: #12323e;
  --color-boston-blue-950: #041e27;
}

SCSS

$boston-blue: #438eac;
$boston-blue-rgb: 67, 142, 172;
$boston-blue-light: mix(#fff, $boston-blue, 20%);
$boston-blue-dark: mix(#000, $boston-blue, 20%);

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