#63A5D1

CSS

:root {
  --sub-zero: #63a5d1;
  --sub-zero-rgb: 99 165 209;
  --sub-zero-oklch: oklch(0.695 0.094 239.3);
}

.element {
  color: var(--sub-zero);
  background-color: hsl(204 54% 60%);
  border-color: oklch(0.695 0.094 239.3);
}

Tailwind CSS v4

@theme {
  --color-sub-zero: #63a5d1;
  --color-sub-zero-50: #def9ff;
  --color-sub-zero-100: #cdedff;
  --color-sub-zero-200: #b1daf9;
  --color-sub-zero-300: #8cbee3;
  --color-sub-zero-400: #68a6d0;
  --color-sub-zero-500: #438ebd;
  --color-sub-zero-600: #3a78a0;
  --color-sub-zero-700: #2e6080;
  --color-sub-zero-800: #1f475f;
  --color-sub-zero-900: #143142;
  --color-sub-zero-950: #051d2b;
}

SCSS

$sub-zero: #63a5d1;
$sub-zero-rgb: 99, 165, 209;
$sub-zero-light: mix(#fff, $sub-zero, 20%);
$sub-zero-dark: mix(#000, $sub-zero, 20%);

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