How to export pdf for custom things?

Hi, experts. I try to make functionallity for download pdf file and the content inside it will be some custom template with images and some table for example. I try to use javascript libraries ( jsPDF for example ) but more of them doesn't support css and this is the problem. The template for pdf file, that how should looked is with css styling. I saw for Jasper ( java library , it is OOB imported ) but I don't know how to work with her. Some one can you helped me, if you know some library to do this or to give me example with 3-4 steps how to use Jasper. Thank you :)