This personal portfolio site was built as part of the Udacity Full-Stack Nano degree. It encompasses many fundamental front-end concepts, including the use of semantic tags, hands on with frameworks like Bootstrap, use of media queries to respond to different devices and improving page performance via the picture element.
As a front-end developer, you will likely have to make many tough calls. For example, do you use Bootstrap when it doesn’t use semantic tags. You could easily use Bootstrap classes on the semantic tags, but what fun is it in learning flex-box and media queries if you don’t write all that CSS yourself. There is also the challenge of using the picture element using Bootstrap. Easy solution. Just write all that CSS yourself! Of course if this was a multi-page website where I had to create repeatable modules, then I’d certainly use Bootsrap.