#5CB9FF

CSS

:root {
  --hello-summer: #5cb9ff;
  --hello-summer-rgb: 92 185 255;
  --hello-summer-oklch: oklch(0.758 0.134 243.7);
}

.element {
  color: var(--hello-summer);
  background-color: hsl(206 100% 68%);
  border-color: oklch(0.758 0.134 243.7);
}

Tailwind CSS v4

@theme {
  --color-hello-summer: #5cb9ff;
  --color-hello-summer-50: #d6faff;
  --color-hello-summer-100: #c4edff;
  --color-hello-summer-200: #a4dbff;
  --color-hello-summer-300: #7bbef8;
  --color-hello-summer-400: #4fa6e7;
  --color-hello-summer-500: #118dd7;
  --color-hello-summer-600: #1578b6;
  --color-hello-summer-700: #126092;
  --color-hello-summer-800: #04476c;
  --color-hello-summer-900: #04314c;
  --color-hello-summer-950: #001d32;
}

SCSS

$hello-summer: #5cb9ff;
$hello-summer-rgb: 92, 185, 255;
$hello-summer-light: mix(#fff, $hello-summer, 20%);
$hello-summer-dark: mix(#000, $hello-summer, 20%);

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