Hi Jean,
If you want certain content outside of the list-content-with-thumb div, just put it into another container and then you can style that separately however you want.
You can view all the CSS/markup in the example site you linked to so maybe just look at that to see how they did it. If you’re using Firefox or Chrome just right click an element and select Inspect Element to view the markup and CSS.
To apply a bottom border to elements you just use: border-bottom: 1px solid #000; on whatever you want to apply the border to. I’m afraid anything else with this you’re on your own. Good luck!
– Jonah