#2D6CC0

CSS

:root {
  --matt-blue: #2d6cc0;
  --matt-blue-rgb: 45 108 192;
  --matt-blue-oklch: oklch(0.535 0.146 256.8);
}

.element {
  color: var(--matt-blue);
  background-color: hsl(214 62% 46%);
  border-color: oklch(0.535 0.146 256.8);
}

Tailwind CSS v4

@theme {
  --color-matt-blue: #2d6cc0;
  --color-matt-blue-50: #dcf7ff;
  --color-matt-blue-100: #cbeaff;
  --color-matt-blue-200: #aed6ff;
  --color-matt-blue-300: #89b9ff;
  --color-matt-blue-400: #63a0f3;
  --color-matt-blue-500: #3e85e5;
  --color-matt-blue-600: #3671c1;
  --color-matt-blue-700: #2b5a9b;
  --color-matt-blue-800: #1a4374;
  --color-matt-blue-900: #112e51;
  --color-matt-blue-950: #041a37;
}

SCSS

$matt-blue: #2d6cc0;
$matt-blue-rgb: 45, 108, 192;
$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);
}