I created React Skill Calculator in May 2020 in order to help beginners determine what they need to learn before they try React. React has many prerequisites and pinpointing exactly what you need to know isn't exactly an easy task. I tried to break things down as much as possible and give the users some options. That's why there are so many options for styling, such as CSS, SASS, LESS and Styled Components.
I had to learn React quickly for my first job, before I was really comfortable with many of the requirements. While I was able to do it, it's not an ideal situation. Not all skills listed in here are mandatory, but they are certainly very helpful.
Here are the skills/technologies I used for this project: HTML, CSS, CSS Box Model, CSS Flexbox, CSS Grid, Media Queries, Styled Components, Ternary Operator and Map Method.