So, if you look in the code, you can see I have added some styles to this page. It would go too far to discuss CSS in detail here. CSS is a very powerful language with which you can do animations and transitions, calculate things, build in
counters, use gradients - basically style the whole page.
I strongly recommend taking a look at the CSS reference and see what the possibilities are. But the best way to learn it is to use it when you need it.