Southern Blue

CSS

:root {
  --southern-blue: #365787;
  --southern-blue-rgb: 54 87 135;
  --southern-blue-oklch: oklch(0.455 0.088 257.7);
}

.element {
  color: var(--southern-blue);
  background-color: hsl(216 43% 37%);
  border-color: oklch(0.455 0.088 257.7);
}

Tailwind CSS v4

@theme {
  --color-southern-blue: #365787;
  --color-southern-blue-50: #e7f6ff;
  --color-southern-blue-100: #d7e9ff;
  --color-southern-blue-200: #bfd6fb;
  --color-southern-blue-300: #9db9e5;
  --color-southern-blue-400: #7ea0d3;
  --color-southern-blue-500: #6187c0;
  --color-southern-blue-600: #5273a2;
  --color-southern-blue-700: #415c82;
  --color-southern-blue-800: #2d4361;
  --color-southern-blue-900: #1f2f44;
  --color-southern-blue-950: #0e1b2c;
}

SCSS

$southern-blue: #365787;
$southern-blue-rgb: 54, 87, 135;
$southern-blue-light: mix(#fff, $southern-blue, 20%);
$southern-blue-dark: mix(#000, $southern-blue, 20%);

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