#636CC8

CSS

:root {
  --loch-ness: #636cc8;
  --loch-ness-rgb: 99 108 200;
  --loch-ness-oklch: oklch(0.568 0.141 276.7);
}

.element {
  color: var(--loch-ness);
  background-color: hsl(235 48% 59%);
  border-color: oklch(0.568 0.141 276.7);
}

Tailwind CSS v4

@theme {
  --color-loch-ness: #636cc8;
  --color-loch-ness-50: #ecf2ff;
  --color-loch-ness-100: #dde4ff;
  --color-loch-ness-200: #c6cfff;
  --color-loch-ness-300: #a7b0ff;
  --color-loch-ness-400: #8a95f0;
  --color-loch-ness-500: #707ae1;
  --color-loch-ness-600: #5f67be;
  --color-loch-ness-700: #4c5399;
  --color-loch-ness-800: #353d72;
  --color-loch-ness-900: #242a51;
  --color-loch-ness-950: #131736;
}

SCSS

$loch-ness: #636cc8;
$loch-ness-rgb: 99, 108, 200;
$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);
}