How to change the code of an element in the browser using python?

Question

Python

I used to come across programs that allowed you to customize the design of pages on your own, change the color scheme in VK, and so on. Viral advertising banners in theory work on the same principle, I would like to write a script (since I am learning to write in Python) that would allow me at the first stages to at least indicate the element code on the input and change its value, so that when I followed the url in the browser (I don’t know yet whether it will work in all browsers or not at the same time), I could change the color of the elements on the pages, are there similar articles or scripts somewhere ready? Where to start xs

Answer 1

Google "userstyle" and "userscript". They are written in CSS and JS, respectively.