#316AAC

CSS

:root {
  --matt-blue: #316aac;
  --matt-blue-rgb: 49 106 172;
  --matt-blue-oklch: oklch(0.519 0.121 253.9);
}

.element {
  color: var(--matt-blue);
  background-color: hsl(212 56% 43%);
  border-color: oklch(0.519 0.121 253.9);
}

Tailwind CSS v4

@theme {
  --color-matt-blue: #316aac;
  --color-matt-blue-50: #dff7ff;
  --color-matt-blue-100: #ceeaff;
  --color-matt-blue-200: #b3d7ff;
  --color-matt-blue-300: #8ebaf5;
  --color-matt-blue-400: #6aa2e4;
  --color-matt-blue-500: #4888d4;
  --color-matt-blue-600: #3e73b3;
  --color-matt-blue-700: #315c90;
  --color-matt-blue-800: #20446b;
  --color-matt-blue-900: #152f4b;
  --color-matt-blue-950: #061b31;
}

SCSS

$matt-blue: #316aac;
$matt-blue-rgb: 49, 106, 172;
$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);
}