Blue Velvet

CSS

:root {
  --blue-velvet: #0d6183;
  --blue-velvet-rgb: 13 97 131;
  --blue-velvet-oklch: oklch(0.464 0.091 232.4);
}

.element {
  color: var(--blue-velvet);
  background-color: hsl(197 82% 28%);
  border-color: oklch(0.464 0.091 232.4);
}

Tailwind CSS v4

@theme {
  --color-blue-velvet: #0d6183;
  --color-blue-velvet-50: #ddfaff;
  --color-blue-velvet-100: #cbeeff;
  --color-blue-velvet-200: #afdbf6;
  --color-blue-velvet-300: #89c0df;
  --color-blue-velvet-400: #64a8cb;
  --color-blue-velvet-500: #3d90b8;
  --color-blue-velvet-600: #357a9b;
  --color-blue-velvet-700: #2a627d;
  --color-blue-velvet-800: #1b485c;
  --color-blue-velvet-900: #123240;
  --color-blue-velvet-950: #041e29;
}

SCSS

$blue-velvet: #0d6183;
$blue-velvet-rgb: 13, 97, 131;
$blue-velvet-light: mix(#fff, $blue-velvet, 20%);
$blue-velvet-dark: mix(#000, $blue-velvet, 20%);

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