#41A5CD

CSS

:root {
  --mystic-blue: #41a5cd;
  --mystic-blue-rgb: 65 165 205;
  --mystic-blue-oklch: oklch(0.68 0.109 228.2);
}

.element {
  color: var(--mystic-blue);
  background-color: hsl(197 58% 53%);
  border-color: oklch(0.68 0.109 228.2);
}

Tailwind CSS v4

@theme {
  --color-mystic-blue: #41a5cd;
  --color-mystic-blue-50: #d7fcff;
  --color-mystic-blue-100: #c4efff;
  --color-mystic-blue-200: #a4defa;
  --color-mystic-blue-300: #7bc2e5;
  --color-mystic-blue-400: #4fabd1;
  --color-mystic-blue-500: #0a93be;
  --color-mystic-blue-600: #127ca1;
  --color-mystic-blue-700: #106481;
  --color-mystic-blue-800: #054a5f;
  --color-mystic-blue-900: #053343;
  --color-mystic-blue-950: #001e2b;
}

SCSS

$mystic-blue: #41a5cd;
$mystic-blue-rgb: 65, 165, 205;
$mystic-blue-light: mix(#fff, $mystic-blue, 20%);
$mystic-blue-dark: mix(#000, $mystic-blue, 20%);

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