Tiffany & Company has announced a three-year renovation of its flagship store on Fifth Avenue, including an expansion of its retail space.

Malls are being hollowed out. Shops are closing by the thousands. Retailers are going bankrupt.

But it may be too early to declare the death of retail. Americans have started shopping more — in stores.

From the garden section at Walmart to the diamond counters at Tiffany & Company, old-school retailers are experiencing some of their best sales growth in years.

The strong revenues start with a roaring economy and an optimistic consumer. Americans, whose wallets are filled with more cash from the tax cuts, have been spending more.

The boom also reflects a broad reordering of the $3.5 trillion industry, with fewer retailers capturing more of the gains. Stores that have learned how to match the ease and instant gratification of e-commerce shopping are flourishing, while those that have failed to evolve are in bankruptcy or on the brink.

“The retailers that get it recognize that Amazon has forever changed consumer behavior,” said Barbara Kahn, a marketing professor and former director of the retailing center at the Wharton School. “I shouldn’t have to work to shop.”

Many successful stores are now a cross between a fast-food drive-through and a hotel concierge.

Target’s shoppers can order sunscreen or a Tokidoki Unicorno T-shirt on their phone, pull up to the parking lot and have the items brought to their car.

Nordstrom lets customers in some stores make returns by dropping their items into a box and walking out — no human interaction required.

Walmart is employing 25,000 “personal shoppers” to select and package groceries for curbside pickup.

In recent weeks, all three retailers reported stronger-than-expected sales growth for the quarter. Traffic to Target’s stores and online sites grew at its fastest pace since the company began keeping a record a decade ago.

Doomsayers have predicted that online shopping, led by Amazon, would one day conquer all of retail, rendering brick and mortar obsolete. As store closings set a record last year, no class of retailer was spared — with the carnage hitting Madison Avenue boutiques, shopping malls and big-box stores.

Sears is among the big retailers that are still struggling, but chains like Target, Walmart and Nordstrom are capitalizing on Amazon-inspired innovations.

But the pace of closings has slowed, as the most unprofitable stores have been culled and the weakest companies have collapsed. At this time in 2017, nearly 5,700 stores had shut across the United States, according to Coresight Research, a retail analysis and advisory firm. So far this year, about 4,480 have closed.

Some big retailers, like J. C. Penney and Sears, are still sputtering, despite closing lagging stores and sprucing up ones that remain open. But the stronger players are capitalizing on the industry’s failures. Target said it was picking up new toy customers in the wake of the…