#636FBC

CSS

:root {
  --loch-ness: #636fbc;
  --loch-ness-rgb: 99 111 188;
  --loch-ness-oklch: oklch(0.567 0.119 275.2);
}

.element {
  color: var(--loch-ness);
  background-color: hsl(232 40% 56%);
  border-color: oklch(0.567 0.119 275.2);
}

Tailwind CSS v4

@theme {
  --color-loch-ness: #636fbc;
  --color-loch-ness-50: #ecf3ff;
  --color-loch-ness-100: #dde5ff;
  --color-loch-ness-200: #c7d0ff;
  --color-loch-ness-300: #a8b2f4;
  --color-loch-ness-400: #8a98e5;
  --color-loch-ness-500: #707ed4;
  --color-loch-ness-600: #5f6bb3;
  --color-loch-ness-700: #4c5590;
  --color-loch-ness-800: #353f6b;
  --color-loch-ness-900: #242b4c;
  --color-loch-ness-950: #131832;
}

SCSS

$loch-ness: #636fbc;
$loch-ness-rgb: 99, 111, 188;
$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);
}