#0F50E9

CSS

:root {
  --opulent-blue: #0f50e9;
  --opulent-blue-rgb: 15 80 233;
  --opulent-blue-oklch: oklch(0.505 0.238 263.2);
}

.element {
  color: var(--opulent-blue);
  background-color: hsl(222 88% 49%);
  border-color: oklch(0.505 0.238 263.2);
}

Tailwind CSS v4

@theme {
  --color-opulent-blue: #0f50e9;
  --color-opulent-blue-50: #d4f5ff;
  --color-opulent-blue-100: #c1e7ff;
  --color-opulent-blue-200: #a3d1ff;
  --color-opulent-blue-300: #7bb1ff;
  --color-opulent-blue-400: #5094ff;
  --color-opulent-blue-500: #2873ff;
  --color-opulent-blue-600: #2362f2;
  --color-opulent-blue-700: #1c4fc3;
  --color-opulent-blue-800: #083a92;
  --color-opulent-blue-900: #052868;
  --color-opulent-blue-950: #001448;
}

SCSS

$opulent-blue: #0f50e9;
$opulent-blue-rgb: 15, 80, 233;
$opulent-blue-light: mix(#fff, $opulent-blue, 20%);
$opulent-blue-dark: mix(#000, $opulent-blue, 20%);

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