A dwindling genre still pushed by naturally rise-averse studios, the young-adult dystopic takes the us-versus-the-world siege mentality of the average teenager and kits it out with hyperbolic, now-predictable apocalyptic flourishes. A mysterious virus; economic breakdown; savage totalitarianism; stirrings of revolution. Adapted from the first novel of Alexandra Bracken’s YA trilogy with a screenplay from Chad Hodge and direction by Kung Fu Panda’s Jennifer Yuh Nelson, The Darkest Minds pits adults against kids with a savageness that’s almost comic. Youngsters either drop dead, get hunted by psycho bounty hunters, or find themselves herded into concentration camps to scrub boots for sociopaths in balaclavas. Even…