Pleasantry fixes

I improved the website experience on mobile, which now has reduced whitespace and text size. Generally you want the mobile experience to show at most one significant element on the page, while also making sure that said element is actually fully on screen. I also changed the showcase tiles to a horizontal list on mobile, as well as adding a link to the actual projects on GitHub, as suggested. Of course, one of the most important changes is that the blogposts feature now finally works! You can click on any blogpost on the main page and it will take you to an expanded content page of said post. It's a bit barebones for now though. Lastly, I fixed a lot of problems for Firefox, as well as making the site more responsive and easier to read. This includes things like the aforementioned horizontal list instead of a vertical one on mobile, and making the introductory slides expandable on mobile as well.