#186EBF

CSS

:root {
  --matt-blue: #186ebf;
  --matt-blue-rgb: 24 110 191;
  --matt-blue-oklch: oklch(0.534 0.148 252.1);
}

.element {
  color: var(--matt-blue);
  background-color: hsl(209 78% 42%);
  border-color: oklch(0.534 0.148 252.1);
}

Tailwind CSS v4

@theme {
  --color-matt-blue: #186ebf;
  --color-matt-blue-50: #d9f8ff;
  --color-matt-blue-100: #c6ebff;
  --color-matt-blue-200: #a8d8ff;
  --color-matt-blue-300: #81bbff;
  --color-matt-blue-400: #58a2f3;
  --color-matt-blue-500: #2b88e4;
  --color-matt-blue-600: #2773c0;
  --color-matt-blue-700: #1f5c9b;
  --color-matt-blue-800: #0f4473;
  --color-matt-blue-900: #0a2f51;
  --color-matt-blue-950: #001b36;
}

SCSS

$matt-blue: #186ebf;
$matt-blue-rgb: 24, 110, 191;
$matt-blue-light: mix(#fff, $matt-blue, 20%);
$matt-blue-dark: mix(#000, $matt-blue, 20%);

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