JS beginner try to write clean code

Hi everyone,

TBH I feel a bit frustrating when I was trying to finish this challenge after finished a udemy course and I thought I can handle this well but turns out I can't. At first I wanted to build this project by using MVC architecture but there is import issue and I can't figure it out so I decided to do it in a beginner way and finally finished it.

Here are some questions, it would be great if you guys could give me some suggestion and comment!

1. would it be better if I use <ul> for container and <li> for comment element?
2. I made a findTargetIndex() function to track the object to modify it's data(since I think I should modify the data instead of just modifing DOM element . Am I right? more like job situation?)
3. But it makes me have to render everything when any data is changed, is there a way only rerender the element is modified?
4. How to modify the fill of the score-plus & score-minus svg

Thanks! (p.s. sorry for my bad naming skill becoz my english is bad and I can't find the right word.)