#45A7B9

CSS

:root {
  --true-sky-blue: #45a7b9;
  --true-sky-blue-rgb: 69 167 185;
  --true-sky-blue-oklch: oklch(0.678 0.094 211.7);
}

.element {
  color: var(--true-sky-blue);
  background-color: hsl(189 46% 50%);
  border-color: oklch(0.678 0.094 211.7);
}

Tailwind CSS v4

@theme {
  --color-true-sky-blue: #45a7b9;
  --color-true-sky-blue-50: #d8fdff;
  --color-true-sky-blue-100: #c5f1fb;
  --color-true-sky-blue-200: #a6dfed;
  --color-true-sky-blue-300: #7dc4d5;
  --color-true-sky-blue-400: #53adbe;
  --color-true-sky-blue-500: #1896aa;
  --color-true-sky-blue-600: #1a7f90;
  --color-true-sky-blue-700: #166673;
  --color-true-sky-blue-800: #0c4b54;
  --color-true-sky-blue-900: #08343b;
  --color-true-sky-blue-950: #001f25;
}

SCSS

$true-sky-blue: #45a7b9;
$true-sky-blue-rgb: 69, 167, 185;
$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);
}