#5F3659

CSS

:root {
  --long-passionate-night: #5f3659;
  --long-passionate-night-rgb: 95 54 89;
  --long-passionate-night-oklch: oklch(0.397 0.078 332.4);
}

.element {
  color: var(--long-passionate-night);
  background-color: hsl(309 28% 29%);
  border-color: oklch(0.397 0.078 332.4);
}

Tailwind CSS v4

@theme {
  --color-long-passionate-night: #5f3659;
  --color-long-passionate-night-50: #ffedfe;
  --color-long-passionate-night-100: #f9dff3;
  --color-long-passionate-night-200: #eac8e2;
  --color-long-passionate-night-300: #d1a9c8;
  --color-long-passionate-night-400: #ba8eb3;
  --color-long-passionate-night-500: #a5739d;
  --color-long-passionate-night-600: #8b6185;
  --color-long-passionate-night-700: #704e6a;
  --color-long-passionate-night-800: #52384f;
  --color-long-passionate-night-900: #392737;
  --color-long-passionate-night-950: #231522;
}

SCSS

$long-passionate-night: #5f3659;
$long-passionate-night-rgb: 95, 54, 89;
$long-passionate-night-light: mix(#fff, $long-passionate-night, 20%);
$long-passionate-night-dark: mix(#000, $long-passionate-night, 20%);

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