page/page.go
func (p PrintToPDFParams) WithMarginBottom(marginBottom float64) *PrintToPDFParams {
	p.MarginBottom = marginBottom
	return &p
}
func (p PrintToPDFParams) WithMarginBottom(marginBottom float64) *PrintToPDFParams {
	p.MarginBottom = marginBottom
	return &p
}
// WithMarginBottom bottom margin in inches. Defaults to 1cm (~0.4 inches).