Css to digia json format conversion

[Satendra9984]

Hello developers, I am making a convertor from css to json for a project to use the properties of css in simple flutter widgets. In css there are many selectors like global, class, inline with many nesting and variable referencing etc. Now to use all that I need a simple css selector for a particular element if parsing eg. div so I need a final simple css for that div so that I can convert its properties in my json format. I am new to html/css world so please can you suggest any approach, packages etc., or I have to write my own parser for that.

Digia format that I need to make finally (this is one example but have to make a general algo)
digia_output.json

html/css (converted in json using html-to-json convertor package in nodejs then I am parsing)
figma_css.json
figma_html.json

Therefore i need as simplified as possible css file so that I can easily parse it for my digia format and I dont know much html/css.
Any other approach or suggestion for solving this problem for html and css parsing both will be very helpful as of now I am planning to use Machine Learning as a second approach.