I have always stood by an opinion that if you have a personal website, it should represent you and only you. I learned HTML/CSS on my own during my studies on primary school and continued to develop my skills during the high school studies. The best example of website design is this site, defwen.com. It has been running since 2011 and I created various themes for it, some based on the premade themes, some from scratch. I also created several website designs for others but most of them ended up not being used. Unfortunately, due to the lack of communication or termination of the project.
Designing a website is one thing, making it run well is another story. I also pay attention to performance and optimizing needed stuff as much as possible (compression, caching, CDN). You can check a performance report of my website at gtmetrix.com to see more information.