updated 02/27/2006 AT 01:00 AM EST
•originally published 02/27/2006 AT 01:00 AM EST
Which was pretty much the same reaction he got in 2003, when he unveiled his first collection as the new women's creative director of Calvin Klein after the legendary namesake stepped down. "Mundane," booed the critics. Fast-forward 2½ years, however, and the take on Costa, 41, has been reversed. His blockbuster Spring 2006 line generated over-the-top reviews and attracted hordes of marquee fans, including Charlize Theron and Sarah Jessica Parker. And after his Feb. 9 Fall '06 show during New York City's Fashion Week, style bible Women's Wear Daily declared that he "has proven himself worthy of the big leagues."
Costa mastered his celebrated balance of minimalism and sensuality by looking to his home country, where "folks dressed simply," recalls the soft-spoken designer. "That's an aesthetic that fits well into Calvin Klein." And one that he's injected with a touch of South American sex appeal: For the Fall '06 show, for example, Costa splashed bold reds throughout the label's more traditional muted palette. "He understands what's sexy," says Tom Ford, who in 1998 hired Costa as a senior designer at Gucci, "what women want to look like and how they want to feel in a dress."
As one of five children growing up in Guarani, a rural mountain town, Costa worked in his family's clothing factory every day, tagging racks and handling garments. "Every other family in town had a siesta. We had to work," says Costa, who would hang out in the fabric room, dreaming up designs. By his teens he was creating clothes and putting on local fashion shows.
Intent on a design career, he came to New York in 1986, studying English by day at Hunter College and taking night classes at the Fashion Institute of Technology, where professors were so wowed they gave him a scholarship. After graduation he honed his fashion chops at Gucci and other powerhouse design shops, including Oscar de la Renta, who says of Costa, "He was always an unbelievably hard worker."
Today, Costa—who shares a Manhattan apartment and Long Island home with his partner, John DeStefano, a horse trainer he met in New York—divides his days among his midtown studio, the European headquarters in Milan and the Madison Avenue store, where fans like Olsen and Julianne Moore pop in to shop. But the first celeb he custom-dressed took some convincing. For a 2004 event at the Metropolitan Museum of Art in New York City, Costa sketched a yellow gown for Johansson, who sent back word that she didn't like it. Costa refused to change the design. "This is what I have to offer," he told her.
In the end Costa once again came out a winner. "She tried on the dress," he says, "and looked fabulous."