As an alternative to the WYSIWYG invoice layout designer (built into the system), you can use another approach in which an invoice template can be designed as an HTML+CSS file and then uploaded into the system (CSS stands for Cascading Style Sheets). This simplifies the process if the invoice template is created by an external design agency (that does not have access to PortaBilling) and allows advanced template customizations (e.g., arrangement of data to exactly match "legacy" invoices or insertion of dynamic content such as banners) by third-party developers. Also we suggest using this approach for large invoices (hundreds of pages and more) as it requires less computing power for PDF file generation in comparison with the WYSIWYG invoice layout designer.
