#406BB9

CSS

:root {
  --song-of-the-sea: #406bb9;
  --song-of-the-sea-rgb: 64 107 185;
  --song-of-the-sea-oklch: oklch(0.536 0.132 261.3);
}

.element {
  color: var(--song-of-the-sea);
  background-color: hsl(219 49% 49%);
  border-color: oklch(0.536 0.132 261.3);
}

Tailwind CSS v4

@theme {
  --color-song-of-the-sea: #406bb9;
  --color-song-of-the-sea-50: #e2f6ff;
  --color-song-of-the-sea-100: #d1e9ff;
  --color-song-of-the-sea-200: #b7d5ff;
  --color-song-of-the-sea-300: #94b7fb;
  --color-song-of-the-sea-400: #729eec;
  --color-song-of-the-sea-500: #5384dc;
  --color-song-of-the-sea-600: #4770ba;
  --color-song-of-the-sea-700: #385995;
  --color-song-of-the-sea-800: #25426f;
  --color-song-of-the-sea-900: #192d4e;
  --color-song-of-the-sea-950: #0a1a34;
}

SCSS

$song-of-the-sea: #406bb9;
$song-of-the-sea-rgb: 64, 107, 185;
$song-of-the-sea-light: mix(#fff, $song-of-the-sea, 20%);
$song-of-the-sea-dark: mix(#000, $song-of-the-sea, 20%);

.element {
  color: $song-of-the-sea;
  box-shadow: 0 0 0 2px rgba($song-of-the-sea, 0.35);
}