When many people read an article on the web, they keep their eyes in one small vertical area on the page and scroll to shift the text (rather than reading the whole visible area and then scrolling to the next "page"). However, when you reach the end of the scroll area, you're suddenly forced to move your eyeline down the page. Adding a bunch of space adds means you can keep scrolling the text to be underneath your eye-area. (sorry for the crufty explanation lol, it's kinda hard to visualize)
Your care and attention to detail are rare things in my experience, and will stand you in good stead in your future career. The effort and love you've put into this project really shine through!
You've put in some good, hard work there, congrats.
I'm thinking I'd have to have some very fine scrolling skills, and sit exactly still to keep my eyes constantly on one small vertical area of the page. And I'd rather dart and exercise my eyeballs than my scrolling finger :)
When you scroll to the bottom while reading text you always only need to look in the middle of the screen when it's padded. Otherwise at the end of the page you would need to look at the bottom of the screen
It means that you can keep your eyeline focussed on the middle of the viewport (or the top, or wherever's natural for you) as you scroll new content into view. On a regular page, once your scrollbar reaches the bottom you have to start reading down the viewport because there's no more space to scroll. I don't know how much practical difference it would actually make to readability - would be interesting to measure - but I thought it was neat
