#5749DC

CSS

:root {
  --warm-blue: #5749dc;
  --warm-blue-rgb: 87 73 220;
  --warm-blue-oklch: oklch(0.513 0.214 280);
}

.element {
  color: var(--warm-blue);
  background-color: hsl(246 68% 57%);
  border-color: oklch(0.513 0.214 280);
}

Tailwind CSS v4

@theme {
  --color-warm-blue: #5749dc;
  --color-warm-blue-50: #ebeeff;
  --color-warm-blue-100: #dce0ff;
  --color-warm-blue-200: #c6c8ff;
  --color-warm-blue-300: #a8a7ff;
  --color-warm-blue-400: #8a89ff;
  --color-warm-blue-500: #7267ff;
  --color-warm-blue-600: #6158e3;
  --color-warm-blue-700: #4d47b7;
  --color-warm-blue-800: #35348a;
  --color-warm-blue-900: #242362;
  --color-warm-blue-950: #131143;
}

SCSS

$warm-blue: #5749dc;
$warm-blue-rgb: 87, 73, 220;
$warm-blue-light: mix(#fff, $warm-blue, 20%);
$warm-blue-dark: mix(#000, $warm-blue, 20%);

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