#4E74B7

CSS

:root {
  --song-of-the-sea: #4e74b7;
  --song-of-the-sea-rgb: 78 116 183;
  --song-of-the-sea-oklch: oklch(0.562 0.113 261.1);
}

.element {
  color: var(--song-of-the-sea);
  background-color: hsl(218 42% 51%);
  border-color: oklch(0.562 0.113 261.1);
}

Tailwind CSS v4

@theme {
  --color-song-of-the-sea: #4e74b7;
  --color-song-of-the-sea-50: #e4f6ff;
  --color-song-of-the-sea-100: #d4e9ff;
  --color-song-of-the-sea-200: #bbd5ff;
  --color-song-of-the-sea-300: #99b8f2;
  --color-song-of-the-sea-400: #789fe1;
  --color-song-of-the-sea-500: #5a85d1;
  --color-song-of-the-sea-600: #4d71b0;
  --color-song-of-the-sea-700: #3d5a8d;
  --color-song-of-the-sea-800: #2a4269;
  --color-song-of-the-sea-900: #1c2e4a;
  --color-song-of-the-sea-950: #0c1a31;
}

SCSS

$song-of-the-sea: #4e74b7;
$song-of-the-sea-rgb: 78, 116, 183;
$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);
}