#91D5D0

CSS

:root {
  --cold-blue: #91d5d0;
  --cold-blue-rgb: 145 213 208;
  --cold-blue-oklch: oklch(0.826 0.069 190.1);
}

.element {
  color: var(--cold-blue);
  background-color: hsl(176 45% 70%);
  border-color: oklch(0.826 0.069 190.1);
}

Tailwind CSS v4

@theme {
  --color-cold-blue: #91d5d0;
  --color-cold-blue-50: #e0fcfa;
  --color-cold-blue-100: #cff0ee;
  --color-cold-blue-200: #b3dedc;
  --color-cold-blue-300: #8ec3c0;
  --color-cold-blue-400: #6daca7;
  --color-cold-blue-500: #499590;
  --color-cold-blue-600: #3f7e7a;
  --color-cold-blue-700: #326562;
  --color-cold-blue-800: #234a47;
  --color-cold-blue-900: #173331;
  --color-cold-blue-950: #081f1d;
}

SCSS

$cold-blue: #91d5d0;
$cold-blue-rgb: 145, 213, 208;
$cold-blue-light: mix(#fff, $cold-blue, 20%);
$cold-blue-dark: mix(#000, $cold-blue, 20%);

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