#6276A3

CSS

:root {
  --misty-harbour: #6276a3;
  --misty-harbour-rgb: 98 118 163;
  --misty-harbour-oklch: oklch(0.568 0.074 265.7);
}

.element {
  color: var(--misty-harbour);
  background-color: hsl(222 26% 51%);
  border-color: oklch(0.568 0.074 265.7);
}

Tailwind CSS v4

@theme {
  --color-misty-harbour: #6276a3;
  --color-misty-harbour-50: #ecf5ff;
  --color-misty-harbour-100: #dde8ff;
  --color-misty-harbour-200: #c6d4f5;
  --color-misty-harbour-300: #a7b7de;
  --color-misty-harbour-400: #8a9ecb;
  --color-misty-harbour-500: #6f85b8;
  --color-misty-harbour-600: #5e719b;
  --color-misty-harbour-700: #4b5a7d;
  --color-misty-harbour-800: #35425c;
  --color-misty-harbour-900: #242e41;
  --color-misty-harbour-950: #131a29;
}

SCSS

$misty-harbour: #6276a3;
$misty-harbour-rgb: 98, 118, 163;
$misty-harbour-light: mix(#fff, $misty-harbour, 20%);
$misty-harbour-dark: mix(#000, $misty-harbour, 20%);

.element {
  color: $misty-harbour;
  box-shadow: 0 0 0 2px rgba($misty-harbour, 0.35);
}