What would you consider to be “modern classics”?

I’m mainly asking about books from the 21st century, but also curious about thoughts on books from towards the end of the 20th century!

Are there books that maybe aren’t considered classics yet but you think they will become classics?

I know we might be working with different definitions of what’s a classic and that’s fine with me! I’m just curious about all of your opinions on this.

Edit: wow this got so much more discussion than I thought it would! Lots of great suggestions; thank you all for making my TBR even longer.

I forgot to include any of my ideas. I think the Hunger Games by Suzanne Collins, The Road by Cormac McCarthy, A Visit from the Goon Squad by Jennifer Egan, and Chain Gang All-Stars by Nana Kwame Adjei-Brenyah are all books I think will be classics; all of these represent aspects of the time when they were written, are well-written, are creative or unique in some way, and are popular.