How to build showcase website faster?

I've made few showcase websites from scratch. Every time it takes a lot of time to build them and a friend told me to not build website with like this. I use Sass and have Javascript/jQuery and PHP basics knowledges.
I don't wan't to use something like Wix because I will not have any control over the code.
I was thinking of something like bootstrap but I find it makes the code overloaded with class names. Can I build my website fondation on this?

What other frameworks/tools can I use to build websites faster?
I want clean code and something that can be fully personalised. It can be for simple showcase websites or something a bit more complex. I also want to know how the code is working.

I'm ready to learn anything new if in the end I would code better and faster. By the way, is there any website/ressource where I can find the trends in web development?