如何使PDF输出看起来与HTML输出完全相同

I am trying to create a PDF for my client to start invoicing their clients. I've dealt with creating PDFs in the past and remember it was a huge pain to create them. In my Django application, I have two view functions, one that just renders a template that I am using to design the invoice, and another that converts it into a pdf and renders the PDF as well. I have two tabs open side by side one that points to each version template HTML vs. PDF and they look completely different. Is there a special Markup language I have to use to create PDFs, or is their a python package out their that converts HTML to an exact replica of that HTML in PDF ?I am trying to create a PDF for my client to st