#426FA1

CSS

:root {
  --naval: #426fa1;
  --naval-rgb: 66 111 161;
  --naval-oklch: oklch(0.532 0.094 252.2);
}

.element {
  color: var(--naval);
  background-color: hsl(212 42% 45%);
  border-color: oklch(0.532 0.094 252.2);
}

Tailwind CSS v4

@theme {
  --color-naval: #426fa1;
  --color-naval-50: #e3f7ff;
  --color-naval-100: #d3eaff;
  --color-naval-200: #b9d7fc;
  --color-naval-300: #97bae7;
  --color-naval-400: #76a2d5;
  --color-naval-500: #5689c2;
  --color-naval-600: #4a74a4;
  --color-naval-700: #3b5d84;
  --color-naval-800: #284462;
  --color-naval-900: #1b2f44;
  --color-naval-950: #0b1c2c;
}

SCSS

$naval: #426fa1;
$naval-rgb: 66, 111, 161;
$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);
}