#4E72C1

CSS

:root {
  --song-of-the-sea: #4e72c1;
  --song-of-the-sea-rgb: 78 114 193;
  --song-of-the-sea-oklch: oklch(0.563 0.129 264.2);
}

.element {
  color: var(--song-of-the-sea);
  background-color: hsl(221 48% 53%);
  border-color: oklch(0.563 0.129 264.2);
}

Tailwind CSS v4

@theme {
  --color-song-of-the-sea: #4e72c1;
  --color-song-of-the-sea-50: #e4f5ff;
  --color-song-of-the-sea-100: #d4e8ff;
  --color-song-of-the-sea-200: #bbd4ff;
  --color-song-of-the-sea-300: #99b6fa;
  --color-song-of-the-sea-400: #779deb;
  --color-song-of-the-sea-500: #5a82db;
  --color-song-of-the-sea-600: #4c6fb9;
  --color-song-of-the-sea-700: #3d5895;
  --color-song-of-the-sea-800: #29416f;
  --color-song-of-the-sea-900: #1b2d4e;
  --color-song-of-the-sea-950: #0c1a34;
}

SCSS

$song-of-the-sea: #4e72c1;
$song-of-the-sea-rgb: 78, 114, 193;
$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);
}