#2C6AC9

CSS

:root {
  --matt-blue: #2c6ac9;
  --matt-blue-rgb: 44 106 201;
  --matt-blue-oklch: oklch(0.536 0.161 259);
}

.element {
  color: var(--matt-blue);
  background-color: hsl(216 64% 48%);
  border-color: oklch(0.536 0.161 259);
}

Tailwind CSS v4

@theme {
  --color-matt-blue: #2c6ac9;
  --color-matt-blue-50: #dbf7ff;
  --color-matt-blue-100: #cae9ff;
  --color-matt-blue-200: #add5ff;
  --color-matt-blue-300: #88b7ff;
  --color-matt-blue-400: #619efc;
  --color-matt-blue-500: #3d83ef;
  --color-matt-blue-600: #356fc9;
  --color-matt-blue-700: #2a59a2;
  --color-matt-blue-800: #184179;
  --color-matt-blue-900: #102d55;
  --color-matt-blue-950: #031a39;
}

SCSS

$matt-blue: #2c6ac9;
$matt-blue-rgb: 44, 106, 201;
$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);
}