#48A5CC

CSS

:root {
  --mystic-blue: #48a5cc;
  --mystic-blue-rgb: 72 165 204;
  --mystic-blue-oklch: oklch(0.682 0.104 228.8);
}

.element {
  color: var(--mystic-blue);
  background-color: hsl(198 56% 54%);
  border-color: oklch(0.682 0.104 228.8);
}

Tailwind CSS v4

@theme {
  --color-mystic-blue: #48a5cc;
  --color-mystic-blue-50: #d8fbff;
  --color-mystic-blue-100: #c6efff;
  --color-mystic-blue-200: #a7ddf9;
  --color-mystic-blue-300: #7ec2e3;
  --color-mystic-blue-400: #54aacf;
  --color-mystic-blue-500: #1e92bd;
  --color-mystic-blue-600: #1e7c9f;
  --color-mystic-blue-700: #186380;
  --color-mystic-blue-800: #0c495e;
  --color-mystic-blue-900: #083342;
  --color-mystic-blue-950: #001e2a;
}

SCSS

$mystic-blue: #48a5cc;
$mystic-blue-rgb: 72, 165, 204;
$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);
}