@timapple While I was thinking about this, I realized that they way I had done it was not very good, so I’ve changed it: glad you asked! Probably the best way to do it is to add some CSS, under Design. Something like this:

.bookshelf-description {
font-size: 1.4rem ;
font-weight: bold ;

You can adjust the 1.4rem up or down, and if the resulting text is too heavy, change “bold” to 500 or 600. And you can get rid of the italics if you want by deleting the asterisks in the JSON file. I hope this helps.