Fluid Blue

CSS

:root {
  --fluid-blue: #c5d6eb;
  --fluid-blue-rgb: 197 214 235;
  --fluid-blue-oklch: oklch(0.87 0.034 253.7);
}

.element {
  color: var(--fluid-blue);
  background-color: hsl(213 49% 85%);
  border-color: oklch(0.87 0.034 253.7);
}

Tailwind CSS v4

@theme {
  --color-fluid-blue: #c5d6eb;
  --color-fluid-blue-50: #eff6ff;
  --color-fluid-blue-100: #e1e9f4;
  --color-fluid-blue-200: #cbd5e3;
  --color-fluid-blue-300: #acb9c9;
  --color-fluid-blue-400: #91a0b3;
  --color-fluid-blue-500: #77889d;
  --color-fluid-blue-600: #657385;
  --color-fluid-blue-700: #505c6a;
  --color-fluid-blue-800: #3a434e;
  --color-fluid-blue-900: #282f36;
  --color-fluid-blue-950: #161b21;
}

SCSS

$fluid-blue: #c5d6eb;
$fluid-blue-rgb: 197, 214, 235;
$fluid-blue-light: mix(#fff, $fluid-blue, 20%);
$fluid-blue-dark: mix(#000, $fluid-blue, 20%);

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