Add extra widget section

I love the Dark News Theme, as it’s exactly what I want for my site. If you look halfway down, you’ll see a standard Widget where I can use categories for posts, which I am using Books, Games, and Movies. I wanted to add another section with that same look for Comics, Music, and Table Games, but I couldn’t duplicate that first Widget section. Instead, I used a category carousel block option in 3 columns. However, it doesn’t look as nice as the first official Widget section. Any idea how to duplicate a theme’s widget?

The page I need help with: [log in to see the link]