#37A8BC

CSS

:root {
  --true-sky-blue: #37a8bc;
  --true-sky-blue-rgb: 55 168 188;
  --true-sky-blue-oklch: oklch(0.677 0.102 211.9);
}

.element {
  color: var(--true-sky-blue);
  background-color: hsl(189 55% 48%);
  border-color: oklch(0.677 0.102 211.9);
}

Tailwind CSS v4

@theme {
  --color-true-sky-blue: #37a8bc;
  --color-true-sky-blue-50: #d5fdff;
  --color-true-sky-blue-100: #c2f1fd;
  --color-true-sky-blue-200: #a1e0ef;
  --color-true-sky-blue-300: #76c5d7;
  --color-true-sky-blue-400: #48aec1;
  --color-true-sky-blue-500: #0097ad;
  --color-true-sky-blue-600: #008092;
  --color-true-sky-blue-700: #006775;
  --color-true-sky-blue-800: #004c56;
  --color-true-sky-blue-900: #01353c;
  --color-true-sky-blue-950: #002026;
}

SCSS

$true-sky-blue: #37a8bc;
$true-sky-blue-rgb: 55, 168, 188;
$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);
}