#4B75B5

CSS

:root {
  --song-of-the-sea: #4b75b5;
  --song-of-the-sea-rgb: 75 117 181;
  --song-of-the-sea-oklch: oklch(0.561 0.11 258.6);
}

.element {
  color: var(--song-of-the-sea);
  background-color: hsl(216 42% 50%);
  border-color: oklch(0.561 0.11 258.6);
}

Tailwind CSS v4

@theme {
  --color-song-of-the-sea: #4b75b5;
  --color-song-of-the-sea-50: #e3f6ff;
  --color-song-of-the-sea-100: #d3e9ff;
  --color-song-of-the-sea-200: #bad6ff;
  --color-song-of-the-sea-300: #97b8f0;
  --color-song-of-the-sea-400: #76a0df;
  --color-song-of-the-sea-500: #5786cf;
  --color-song-of-the-sea-600: #4a72ae;
  --color-song-of-the-sea-700: #3b5b8c;
  --color-song-of-the-sea-800: #284368;
  --color-song-of-the-sea-900: #1b2e49;
  --color-song-of-the-sea-950: #0b1b30;
}

SCSS

$song-of-the-sea: #4b75b5;
$song-of-the-sea-rgb: 75, 117, 181;
$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);
}