Amazon’s sway in the publishing world now extends to even the design of books themselves. The company now accounts for about 45% of all books sold in the U.S., according to Peter Hildick-Smith, president of industry researcher Codex-Group, LLC.

As Amazon’s importance as a bookseller has grown, publishers are pushing their designers for brighter, bolder covers that pop for online shoppers. That has led to a spate of brightly colored book jackets, with blaring yellow covers now appearing in profusion.

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