#3A7574

CSS

:root {
  --tropical-rain: #3a7574;
  --tropical-rain-rgb: 58 117 116;
  --tropical-rain-oklch: oklch(0.523 0.062 194);
}

.element {
  color: var(--tropical-rain);
  background-color: hsl(179 34% 34%);
  border-color: oklch(0.523 0.062 194);
}

Tailwind CSS v4

@theme {
  --color-tropical-rain: #3a7574;
  --color-tropical-rain-50: #e2fbfb;
  --color-tropical-rain-100: #d1efee;
  --color-tropical-rain-200: #b7dddd;
  --color-tropical-rain-300: #93c2c2;
  --color-tropical-rain-400: #72aaa9;
  --color-tropical-rain-500: #519392;
  --color-tropical-rain-600: #457d7b;
  --color-tropical-rain-700: #376463;
  --color-tropical-rain-800: #274948;
  --color-tropical-rain-900: #1a3332;
  --color-tropical-rain-950: #0a1e1e;
}

SCSS

$tropical-rain: #3a7574;
$tropical-rain-rgb: 58, 117, 116;
$tropical-rain-light: mix(#fff, $tropical-rain, 20%);
$tropical-rain-dark: mix(#000, $tropical-rain, 20%);

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