Custom CSS Theming

I found it particularly hard to get my head around the HTML and CSS coding files due to so much information already there. It was especially hard trying to figure out if I was adding to the right part of the code. There were times when I would change or add things, and nothing would happen, which became frustrating and I'd have to sit through trying to find out where I had gone wrong. I ended up only changing minor things like font styles and colours, but I felt happy seeing the code work in action. HTML was interesting to learn about, even if it was only the basics. However, I'll need a lot more time with it to feel comfortable doing anything more advanced.