#071049

CSS

:root {
  --storm: #071049;
  --storm-rgb: 7 16 73;
  --storm-oklch: oklch(0.216 0.105 267.9);
}

.element {
  color: var(--storm);
  background-color: hsl(232 83% 16%);
  border-color: oklch(0.216 0.105 267.9);
}

Tailwind CSS v4

@theme {
  --color-storm: #071049;
  --color-storm-50: #e9f5ff;
  --color-storm-100: #dae7ff;
  --color-storm-200: #c2d3ff;
  --color-storm-300: #a2b5ee;
  --color-storm-400: #849cdd;
  --color-storm-500: #6883cc;
  --color-storm-600: #586fac;
  --color-storm-700: #46588a;
  --color-storm-800: #314167;
  --color-storm-900: #212d48;
  --color-storm-950: #111a2f;
}

SCSS

$storm: #071049;
$storm-rgb: 7, 16, 73;
$storm-light: mix(#fff, $storm, 20%);
$storm-dark: mix(#000, $storm, 20%);

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