#5669AB

CSS

:root {
  --loch-ness: #5669ab;
  --loch-ness-rgb: 86 105 171;
  --loch-ness-oklch: oklch(0.536 0.106 270.4);
}

.element {
  color: var(--loch-ness);
  background-color: hsl(227 34% 50%);
  border-color: oklch(0.536 0.106 270.4);
}

Tailwind CSS v4

@theme {
  --color-loch-ness: #5669ab;
  --color-loch-ness-50: #eaf4ff;
  --color-loch-ness-100: #dbe6ff;
  --color-loch-ness-200: #c4d2ff;
  --color-loch-ness-300: #a4b4ee;
  --color-loch-ness-400: #869bde;
  --color-loch-ness-500: #6b81cd;
  --color-loch-ness-600: #5b6ead;
  --color-loch-ness-700: #49588b;
  --color-loch-ness-800: #334067;
  --color-loch-ness-900: #222c49;
  --color-loch-ness-950: #121930;
}

SCSS

$loch-ness: #5669ab;
$loch-ness-rgb: 86, 105, 171;
$loch-ness-light: mix(#fff, $loch-ness, 20%);
$loch-ness-dark: mix(#000, $loch-ness, 20%);

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