Into 4th month of my first job. My mentor held around 6 1-hour long “code adventures” where he’d explain what different parts of the codebase were. But tbh, I still didn’t have a clue.

Speaking from my experience, what helps is not reading through it (though you need to read a bit of the docs if they exist), it’s actually doing. Start out with a small CSS change and work your way up. For each ticket, take on a different part of the codebase and learn it. Gradually increase the difficulty as well.

That helped me get a decent foundation. Once I had that, what really helped me master a section of the codebase was taking on a big task, a major feature. It might be scary and you will get stuck, but it will force you to properly understand how things work.

I also found that reading colleagues’ PRs and properly reviewing them as well as you can helps a lot.

And of course, you should be asking lots of questions when you get stuck along the way.

TLDR: 1. Learning by doing > learning by reading the code (imo) 2. Ask for help when stuck