/* Change only these two parameters. Preset hues: purple 236, blue 216,
   orange 25, green 145. Saturation controls the intensity (0%–100%). */
:root {
  --brand-hue: 236;
  --brand-saturation: 65%;

  /* Accessible dark accent, pale surfaces and borders derived from the brand. */
  --brand: hsl(var(--brand-hue) var(--brand-saturation) 36%);
  --brand-soft: hsl(var(--brand-hue) var(--brand-saturation) 96%);
  --brand-border: hsl(var(--brand-hue) calc(var(--brand-saturation) * .7) 72%);
  --flow-arrow: hsl(var(--brand-hue) calc(var(--brand-saturation) * 0.719) 66.86%);
}