#45737A

CSS

:root {
  --ocean-slumber: #45737a;
  --ocean-slumber-rgb: 69 115 122;
  --ocean-slumber-oklch: oklch(0.525 0.052 208);
}

.element {
  color: var(--ocean-slumber);
  background-color: hsl(188 28% 37%);
  border-color: oklch(0.525 0.052 208);
}

Tailwind CSS v4

@theme {
  --color-ocean-slumber: #45737a;
  --color-ocean-slumber-50: #e5fafd;
  --color-ocean-slumber-100: #d5edf1;
  --color-ocean-slumber-200: #bcdbe0;
  --color-ocean-slumber-300: #9abfc6;
  --color-ocean-slumber-400: #7ba7ae;
  --color-ocean-slumber-500: #5c9098;
  --color-ocean-slumber-600: #4e7a81;
  --color-ocean-slumber-700: #3e6267;
  --color-ocean-slumber-800: #2c484b;
  --color-ocean-slumber-900: #1e3234;
  --color-ocean-slumber-950: #0e1e20;
}

SCSS

$ocean-slumber: #45737a;
$ocean-slumber-rgb: 69, 115, 122;
$ocean-slumber-light: mix(#fff, $ocean-slumber, 20%);
$ocean-slumber-dark: mix(#000, $ocean-slumber, 20%);

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