#5668B2

CSS

:root {
  --loch-ness: #5668b2;
  --loch-ness-rgb: 86 104 178;
  --loch-ness-oklch: oklch(0.538 0.118 271.6);
}

.element {
  color: var(--loch-ness);
  background-color: hsl(228 37% 52%);
  border-color: oklch(0.538 0.118 271.6);
}

Tailwind CSS v4

@theme {
  --color-loch-ness: #5668b2;
  --color-loch-ness-50: #eaf4ff;
  --color-loch-ness-100: #dbe6ff;
  --color-loch-ness-200: #c4d1ff;
  --color-loch-ness-300: #a4b3f4;
  --color-loch-ness-400: #869ae4;
  --color-loch-ness-500: #6b80d4;
  --color-loch-ness-600: #5a6cb3;
  --color-loch-ness-700: #485790;
  --color-loch-ness-800: #32406b;
  --color-loch-ness-900: #222c4b;
  --color-loch-ness-950: #111932;
}

SCSS

$loch-ness: #5668b2;
$loch-ness-rgb: 86, 104, 178;
$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);
}