To make their Barbieland sets a reality, the movie’s production team embraced the surreal, going big on bright pinks and shrunken proportions.While working on films like “Atonement,” “Anna Karenina” and “Darkest Hour,” the production designer Sarah Greenwood and the set decorator Katie Spencer, both Oscar nominees many times over, had to turn soundstages into period-accurate sets, using their extraordinary attention to detail to embroider these spaces with texture and soul.And while those jobs were demanding — if even one thing looked wrong, it could dispel the film’s period illusion — they proved to be no match for the bright-pink studio comedy that is Greta Gerwig’s “Barbie.”“It was one of the most difficult philosophical, intellectual, cerebral pieces of work we’ve ever done,” Greenwood told me last week during a video call with Spencer. “How can that be? It’s ‘Barbie.’ But it really was.”Then again, since the film works on several levels, many things about “Barbie” are headier than you might expect: Though it’s a big-budget film based on a Mattel toy, Gerwig and her co-writer, Noah Baumbach, pose plenty of significant questions about life and womanhood throughout. And in the visually dazzling Barbie Dreamhouses that Greenwood and Spencer designed — where Margot Robbie, as Barbie, and Ryan Gosling, as Ken, performed — even the smallest details in the background required many months of existential pondering.“Everything is considered,” Spencer said. “Absolutely everything.”Though Gerwig came on board the project as a bona fide Barbie aficionado, Greenwood and Spencer had no personal history with the doll. “Neither of us had Barbie growing up,” Spencer said. “I suppose we were like a lot of the population, quite judgmental about Barbie in a way.”The film’s primary color was a vivid fuchsia. The production cleaned its paint supplier out of every pail they had.Warner Bros.Still, captivated by Gerwig’s enthusiasm, the two women threw themselves into intense research. Their directive was to preserve a sense of play, which is why Barbie’s home has no stairs: Why would a doll deign to descend a flight of steps when she could take a circular pink slide or, even better, float gracefully down from the roof as if guided by the invisible hand of a child?“We all had to believe in it as much as if it was a space movie or period movie,” Spencer said. “We had to research it as though it was set in 1780.”First, the designers studied a vintage Barbie Dreamhouse, finding it to be much more cramped than they anticipated: A classically proportioned Barbie could graze the ceiling of each room with a simple upward swivel of her arm.To simulate that feel, “the Dreamhouses in the film are 23 percent smaller than they would be, as are the cars and roads,” Greenwood said. “When you scale the house down, you make the actors like Margot and Ryan seem bigger, which makes the whole thing seem ‘toy.’”Instead of adapting the Dreamhouses to feel more real, Greenwood and Spencer played up their surreality. When Barbie opens her refrigerator, most of the foods are simply flat cartoon decals. Her oversize cup contains no liquid — why should it, when Barbies don’t drink? — and the size of her toothbrush is even more exaggerated, since it’s the kind of prop a child might find included in a dollhouse.“Once you’ve done that once or twice, those moments of dollness, it makes the whole thing believable,” Spencer said.With few walls to speak of, Barbie Dreamhouses are the definition of “open plan,” which presented its own logistical problems. “You’re designing something that isn’t there, in effect,” said Greenwood, who drew inspiration from museum dioramas to conjure layers of background that would help fill each shot. Since our main Barbies live in a cul-de-sac — in fact, it’s the dot of the “i” in the cursive roads that spell “Barbieland” — each Dreamhouse looks out into several other Dreamhouses, while the blue sky and mauve mountains that surround them were hand-painted onto an 800-foot-long backdrop meant to recall old-fashioned soundstage musicals.If it feels artificial, that’s the point: Why preserve the fourth wall for homes that barely have any walls to begin with? “It’s fake-fake, which is perfect,” Greenwood said. “It was almost Brechtian, the way Greta approached it.”Kate McKinnon as Weird Barbie. Her home stands in contrast to the style of the film’s Barbie Dreamhouses.Warner Bros.There is no actual fire in Barbie’s fireplace, nor water in her pool, since Barbieland is devoid of all elements and is as hermetically sealed as a toy box. There aren’t even whites, blacks or browns: Anything in a Dreamhouse that would typically be those colors is just a different shade of pink, with a primary fuchsia so vivid that the production cleaned its paint supplier out of every pail they had.“All the other colors, like the blues, had to up the ante,” Greenwood said, referring to their intensity.The cul-de-sac Dreamhouses were designed in a midcentury-modern style that evokes the time period when Barbie was invented. “We kept coming back to the aesthetic of Palm Springs,” Spencer said. In contrast to those homes, distinguished by clean and simple lines, was the postmodern house on a hill owned by Weird Barbie (Kate McKinnon) — a riot of weird angles and clashing colors, as if Pee-wee’s Playhouse emerged in the middle of a carefully constructed pop-up book.“It was once a Dreamhouse, and it all went a little bit cockeyed, like her,” Greenwood said. “Nothing there was straight, in any sense of the word.”Like its owner, whose face is covered in scribble marks, the walls of Weird Barbie’s house are adorned in doodle patterns and swirls, and there are plenty of other colors on display besides pink. (The primary color on one wall is even, gasp, green.) The other Barbies treat her domicile as if it were a witch’s house, but you can’t deny that Weird Barbie has an eye. Greenwood and Spencer singled out her irregular rainbow rug as a favorite that everyone hoped to take home.“We all wanted her rug, but it’s gone into the Warner Bros. vault of goods,” Spencer said. “But I love the fact that in this vault where you have to go through so much security, you have the Batmobile and then you have Barbie’s car.”Weird Barbie’s house isn’t the movie’s only deviation: Later in the story, after a trip to the real world tips off Ken to the power of the patriarchy, he returns home and exhorts the other Kens to turn the pink and girlie Barbieland into their own personal “Ken-dom.” Soon enough, they’ve staged a hostile takeover of the Dreamhouses — rechristened the “Mojo Dojo Casa Houses” — and given those buildings a man-cave makeover replete with La-Z-Boys, mini fridges and appalling equestrian lampshades.From left, Kingsley Ben-Adir, Ryan Gosling and Ncuti Gatwa, three of the film’s Kens.Warner Bros. “We had to keep going back to Greta and saying, really? Really ugly?” Greenwood said. “But there’s a purity to the ugliness as well, because it’s a limited palate.”That’s because these himbos aren’t sure where all of their purloined swag ought to go, or even what most of it does. Barbecues have been placed haphazardly onto ovens, the juicers are filled with Doritos, and flat-screen TVs in every Mojo Dojo Casa House are tuned to the same hypnotically banal clip of a horse in eternal gallop.”He’s no interior designer, Ken,” Spencer said, chuckling. “But can I just say, a lot of the crew wanted to buy things from the Ken-dom. I’m not saying who, but a lot of them did.”The film was shot last year at Warner Bros.’s Leavesden Studios, about 20 miles northwest of London, and as word of the colorful sets spread, the production quickly attracted its fair share of visitors. “We were filming in an English winter, gray and black with snow,” Greenwood said. “So everybody would just come in there for an injection of light and summer.”Added Spencer: “It made people happy. You couldn’t help but smile.”And what of its makers? Did all that time spent on these “Barbie” sets affect their personal palette? Yes, confessed Greenwood.“I’ve painted my bedroom pink, literally,” she said. “I’d never painted anything pink before. I love pink now!” More