You could just try to get some more investment by sending "Interesting. What do you like to read?".

max's line is super solid but you could also just use a transition like "You mean you weren't wearing them for fun? So how's your wild weekend been thus far?" (or whatever day it is)

a couple of other response options "Ahh reading an actual book, such a lost art. So how's your wild weekend been thus far book lady?"
or "Ahh reading an actual book, such a lost art. Are you a trendsetter?"

Lastly, I use the line "I like your style & those sexy nerd glasses." sometimes it will help with getting such a generic response but be prepared to respond to a lot of varations of Thanks or Thank you.

The point of an opener is to open, if you don't want to continue the thread just switch topics

She carried her half of the conversation with that reply, you're lucky to have gotten that much off that opening, if you think it's bland recalibrate and prepare to work harder!

I would have fired back "you just tryna seduce me with hot librarian energy" but I'm actually into hot librarian energy...