#437099

CSS

:root {
  --naval: #437099;
  --naval-rgb: 67 112 153;
  --naval-oklch: oklch(0.531 0.082 247.4);
}

.element {
  color: var(--naval);
  background-color: hsl(209 39% 43%);
  border-color: oklch(0.531 0.082 247.4);
}

Tailwind CSS v4

@theme {
  --color-naval: #437099;
  --color-naval-50: #e4f8ff;
  --color-naval-100: #d4ebff;
  --color-naval-200: #bad8f7;
  --color-naval-300: #98bbe0;
  --color-naval-400: #77a3cd;
  --color-naval-500: #588bba;
  --color-naval-600: #4b769d;
  --color-naval-700: #3c5e7e;
  --color-naval-800: #29455d;
  --color-naval-900: #1c3041;
  --color-naval-950: #0c1c2a;
}

SCSS

$naval: #437099;
$naval-rgb: 67, 112, 153;
$naval-light: mix(#fff, $naval, 20%);
$naval-dark: mix(#000, $naval, 20%);

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