#25A9C3

CSS

:root {
  --true-sky-blue: #25a9c3;
  --true-sky-blue-rgb: 37 169 195;
  --true-sky-blue-oklch: oklch(0.679 0.112 215);
}

.element {
  color: var(--true-sky-blue);
  background-color: hsl(190 68% 45%);
  border-color: oklch(0.679 0.112 215);
}

Tailwind CSS v4

@theme {
  --color-true-sky-blue: #25a9c3;
  --color-true-sky-blue-50: #d2feff;
  --color-true-sky-blue-100: #bef2ff;
  --color-true-sky-blue-200: #9de1f4;
  --color-true-sky-blue-300: #6fc6dd;
  --color-true-sky-blue-400: #3bafc8;
  --color-true-sky-blue-500: #0098b4;
  --color-true-sky-blue-600: #008098;
  --color-true-sky-blue-700: #00677a;
  --color-true-sky-blue-800: #004c59;
  --color-true-sky-blue-900: #00353e;
  --color-true-sky-blue-950: #002028;
}

SCSS

$true-sky-blue: #25a9c3;
$true-sky-blue-rgb: 37, 169, 195;
$true-sky-blue-light: mix(#fff, $true-sky-blue, 20%);
$true-sky-blue-dark: mix(#000, $true-sky-blue, 20%);

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