Stay the Night

CSS

:root {
  --stay-the-night: #314662;
  --stay-the-night-rgb: 49 70 98;
  --stay-the-night-oklch: oklch(0.39 0.055 255.9);
}

.element {
  color: var(--stay-the-night);
  background-color: hsl(214 33% 29%);
  border-color: oklch(0.39 0.055 255.9);
}

Tailwind CSS v4

@theme {
  --color-stay-the-night: #314662;
  --color-stay-the-night-50: #ecf6ff;
  --color-stay-the-night-100: #dde9fb;
  --color-stay-the-night-200: #c6d6ec;
  --color-stay-the-night-300: #a6b9d4;
  --color-stay-the-night-400: #89a0bf;
  --color-stay-the-night-500: #6e88ab;
  --color-stay-the-night-600: #5e7390;
  --color-stay-the-night-700: #4b5c74;
  --color-stay-the-night-800: #354455;
  --color-stay-the-night-900: #242f3b;
  --color-stay-the-night-950: #131b25;
}

SCSS

$stay-the-night: #314662;
$stay-the-night-rgb: 49, 70, 98;
$stay-the-night-light: mix(#fff, $stay-the-night, 20%);
$stay-the-night-dark: mix(#000, $stay-the-night, 20%);

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