#99D4FF

CSS

:root {
  --clear-sky: #99d4ff;
  --clear-sky-rgb: 153 212 255;
  --clear-sky-oklch: oklch(0.845 0.085 240.7);
}

.element {
  color: var(--clear-sky);
  background-color: hsl(205 100% 80%);
  border-color: oklch(0.845 0.085 240.7);
}

Tailwind CSS v4

@theme {
  --color-clear-sky: #99d4ff;
  --color-clear-sky-50: #e1f9ff;
  --color-clear-sky-100: #d0ecff;
  --color-clear-sky-200: #b5d9f6;
  --color-clear-sky-300: #91bde0;
  --color-clear-sky-400: #6fa5cc;
  --color-clear-sky-500: #4d8db9;
  --color-clear-sky-600: #42789d;
  --color-clear-sky-700: #35607e;
  --color-clear-sky-800: #24465d;
  --color-clear-sky-900: #183141;
  --color-clear-sky-950: #081d2a;
}

SCSS

$clear-sky: #99d4ff;
$clear-sky-rgb: 153, 212, 255;
$clear-sky-light: mix(#fff, $clear-sky, 20%);
$clear-sky-dark: mix(#000, $clear-sky, 20%);

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