#646CC9

CSS

:root {
  --loch-ness: #646cc9;
  --loch-ness-rgb: 100 108 201;
  --loch-ness-oklch: oklch(0.57 0.142 277.2);
}

.element {
  color: var(--loch-ness);
  background-color: hsl(235 48% 59%);
  border-color: oklch(0.57 0.142 277.2);
}

Tailwind CSS v4

@theme {
  --color-loch-ness: #646cc9;
  --color-loch-ness-50: #ecf2ff;
  --color-loch-ness-100: #dde4ff;
  --color-loch-ness-200: #c7ceff;
  --color-loch-ness-300: #a8b0ff;
  --color-loch-ness-400: #8a95f1;
  --color-loch-ness-500: #7179e2;
  --color-loch-ness-600: #5f67bf;
  --color-loch-ness-700: #4c5299;
  --color-loch-ness-800: #353c73;
  --color-loch-ness-900: #242a51;
  --color-loch-ness-950: #131736;
}

SCSS

$loch-ness: #646cc9;
$loch-ness-rgb: 100, 108, 201;
$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);
}