NEW YORK • Mariuccia Mandelli, an Italian fashion designer whose long list of credits includes the shortest of achievements - she was widely described as having invented hot pants - died on Sunday at her home in Milan. She was 90.

In a statement, Italian Prime Minister Matteo Renzi paid tribute to her.

Mandelli, a former schoolteacher and self-taught designer, founded the fashion house Krizia in the mid-1950s. She reigned for decades as "the godmother of classic Milanese fashion", as Newsweek described her in 1987.

One of Italy's first ready-to-wear houses, Krizia - known for designs that combined wit, whimsy and wearability - helped secure the country's place in the fashion firmament. At its height in the 1990s, Krizia was a US$500 milliona-year business, with a string of retail shops worldwide and a spate of branded products that included eyeglasses, neckties, furniture and perfumes.

Last year, its fortunes waning, the company was sold to Chinese retail group Shenzhen Marisfrolg Fashion.

Hallmarks of the Krizia style included classic tailoring - often entailing structured, sculptural shoulders - combined with a looserfitting, comfortable cut throughout a garment. Mandelli had a passion for pleats, which could run in unorthodox directions, and for unusual materials, including metallics, rubber, snakeskin, eel skin and even cork.

Krizia became especially well known for knitwear and in particular for Mandelli's sweaters bearing fanciful images of animals, a different one each season. (She was afraid of animals, she often said, and could bear them only as representations.) Over the years, the sweaters, which became highly collectible, featured a veritable Noah's ark: lions, tigers, leopards, parrots, toucans, elephants, dogs, cats, apes and dinosaurs.

Mandelli was attracted to dimensional extremes.

"Either very short or very long," she told The New York Times in 1987. "Either tight or loose."

For her, the zenith of very shortness came just before New Year in 1971, when she introduced the garment that would come to be known as hot pants.

Unlike conventional shorts, hot pants had no waistband and were often made of sumptuous fabrics such as satin or velvet. They also had minimal vertical reach.

While hot pants may simply have been an ubiquitous idea whose time had come, the fashion press, including Women's Wear Daily in its obituary on Monday, overwhelmingly credited Mandelli with its invention.

In a January 1971 article about the hot-pants phenomenon, The Times wrote: "Stores that got in early with the new craze are reporting a surprising amount of interest in their shorts departments, whether they're calling the garment 'Cool Pants' (Bergdorf's), 'Shortcuts' (Bloomingdale's) or 'Hot Pants' (Ohrbach's, Alexander's). Cold weather seems not to be deterring women who want to be first with a new fad." Husbands, The Times added, were encouraging their wives to buy them.

Mandelli was born in Bergamo, near Milan. A gifted amateur seamstress, she trained to be a teacher at her mother's insistence. In the mid1950s, after teaching for several years, she was offered the use of a friend's Rome apartment, rent-free, for six months.

She quit her job, borrowed money, bought a sewing machine and sold the clothes she made from the back of her Fiat 500. She named her company Krizia after a character in a dialogue by Plato about women's vanity.

In 1964, at the Palazzo Pitti in Florence, her all-black-and-white collection won a prestigious fashion prize, the Critica della Moda award, cementing Krizia's international reputation. Over time, she became one of the few high-profile female designers for women who also created successful menswear collections.

Mandelli made headlines in the mid-1990s when she was tried, along with executives of several other prominent Italian design houses, on charges of having bribed tax officials. (The defendants maintained that the officials had been extorting them.) Convicted, she received a suspended sentence; her conviction was later overturned.

Information on her survivors was unavailable. Her husband Aldo Pinto, whom she married in the 1960s, served for many years as Krizia's chairman.

The designer, who often described herself as a feminist and a socialist, owned a publishing house that issued Italian translations of books by writers such as Virginia Woolf and Doris Lessing.

She also founded and designed the K Club, a luxury resort on Barbuda in the Caribbean, whose guests have included the late Princess Diana.

If there was a unifying ethos underlying Mandelli's fashion, it was, she said, that nothing should feel forced - neither for the designer nor for the wearer.

"I would be ashamed to tell women, 'You must dress like this or like that because it is the year's fashion,'" she said in an interview quoted by The Chicago Tribune in 1987. "Everyone must dress as they like, provided the dress becomes for them a second skin."

NEW YORK TIMES