#5E9FC8

CSS

:root {
  --sub-zero: #5e9fc8;
  --sub-zero-rgb: 94 159 200;
  --sub-zero-oklch: oklch(0.675 0.09 237.8);
}

.element {
  color: var(--sub-zero);
  background-color: hsl(203 49% 58%);
  border-color: oklch(0.675 0.09 237.8);
}

Tailwind CSS v4

@theme {
  --color-sub-zero: #5e9fc8;
  --color-sub-zero-50: #dff9ff;
  --color-sub-zero-100: #ceedff;
  --color-sub-zero-200: #b2daf7;
  --color-sub-zero-300: #8dbee1;
  --color-sub-zero-400: #69a6ce;
  --color-sub-zero-500: #458ebb;
  --color-sub-zero-600: #3b799e;
  --color-sub-zero-700: #2f607f;
  --color-sub-zero-800: #1f475d;
  --color-sub-zero-900: #153141;
  --color-sub-zero-950: #061d2a;
}

SCSS

$sub-zero: #5e9fc8;
$sub-zero-rgb: 94, 159, 200;
$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);
}