#6372A9

CSS

:root {
  --loch-ness: #6372a9;
  --loch-ness-rgb: 99 114 169;
  --loch-ness-oklch: oklch(0.563 0.087 271.7);
}

.element {
  color: var(--loch-ness);
  background-color: hsl(227 29% 53%);
  border-color: oklch(0.563 0.087 271.7);
}

Tailwind CSS v4

@theme {
  --color-loch-ness: #6372a9;
  --color-loch-ness-50: #edf4ff;
  --color-loch-ness-100: #dee7ff;
  --color-loch-ness-200: #c8d2fa;
  --color-loch-ness-300: #a9b5e5;
  --color-loch-ness-400: #8c9cd3;
  --color-loch-ness-500: #7182c0;
  --color-loch-ness-600: #606ea2;
  --color-loch-ness-700: #4d5882;
  --color-loch-ness-800: #364161;
  --color-loch-ness-900: #252d44;
  --color-loch-ness-950: #141a2c;
}

SCSS

$loch-ness: #6372a9;
$loch-ness-rgb: 99, 114, 169;
$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);
}