docs: function maxZIndexInUse() {
    const elements = document.body.querySelectorAll('*');
    const zIndices = Array.from(elements, element => {
      const style = getComputedStyle(element);
      let zIndex = 0;
      if (style.position !== 'static' && style.zIndex !== 'auto') {
        const parsed = style.zIndex ? parseInt(style.zIndex) : 0;
        zIndex = !isNaN(parsed) ? parsed : 0;
      }
      return zIndex;
    });
    return Math.max(...zIndices);
  }