What do teens want for Christmas? Whatever Kylie Jenner's pitching on Instagram. (Rick Kern/Getty Images for Ulta Beauty)

Like many her age, Lucia Valderrabano’s Christmas list is a curated collection of screen shots — snippets of this season’s trendiest items plucked from Instagram, YouTube and other social media.

At the top of her list is the Burgundy Extended Palette by Kylie Cosmetics. To the untrained eye, the $45 compact is just 12 vaguely similar eye shadows.

To Lucia, 14, the rosy hues are the key to creating the perfect Kylie Jenner look. (“I want it so badly,” she said.) Also high on the list are Glossier lip gloss, body wash and lip balm. (“I want everything, really.”)

Lucia is hoping her parents are feeling generous — but there’s also a chance her friends will come through. They are planning a Secret Santa exchange, and everyone has pretty much the same promoted-by-Instagram wish list.

Say goodbye to window shopping with family members or hitting the mall with friends to spend holiday cash. Now, when scouting gifts galore, the preferred method is to open Instagram . . . and scroll.

Of course, these shoppers aren’t drawn to a new eye shadow palette or Nike sneakers by some fluke. They are a captive audience for celebrities — whether promoting their own brands or paid by retailers to promote theirs — who push out a stream of ads and promotions.

That eye shadow from Jenner? Her fans first saw it in a high-gloss selfie she posted online. Her face fills the screen, giving a sense of intimacy and immediacy. Except for the slick feel, it doesn’t look like advertising. And you might not know it is unless you click on the photo to see the caption, which inevitably names the product she’s pitching and announces a launch date or special promotion for it.

Top those promotions off with social media’s advertising algorithms — ones scarily attuned to your tastes -- and it’s hard to stop scrolling.

At the top of 15-year-old Anna Gustafson’s holiday list is a light brown pixie coat by I Am Gia -- the one that’s seemingly taken over Instagram. Anna can quickly pull up images from Rihanna’s Instagram account showing the singer pursing her perfectly polished lips to promote the latest shade of her Gloss Bomb series: FU$$Y. Anna also asked for oversize sweatshirts from Shadow Hill, ones she’s seen promoted by YouTube sensations Olivia Jade and Mel Joy.

Millions of photos and videos go up on Instagram each day, but the posts have a way of steering shoppers to exactly what they’re looking for — shade, size, brand — leaving little need to browse a mall and check out items in person.

Anna’s mother, Carrie O’Neill, said she’s watched her daughter do less of her shopping in stores, even as her holiday wish list grows more specific. The only exception? Anna’s desire for gift cards to clothing stores so that she could pick out exactly what she wanted herself, O’Neill said.

“It’s not just ‘this lipstick,’ ” O’Neill said. “It’s ‘this lipstick by this person from Sephora.’ Or ‘this jacket by this designer in this color and size.’ ”

It’s clear that social media is shaping shopping habits even beyond the holidays, and particularly for younger consumers.

“There’s a change in behavior through online shopping,” said Alexis DeSalva, a retail and e-commerce expert at Mintel. “We know that social media is part of the process for a lot of people.”

Celebrities and influencers know how the game is played — or, more accurately, how to run the table themselves. Lucia said she’s kept an eye on holiday discount codes posted to some of her favorite accounts. For example, Kylie Cosmetics took to Instagram this month to tell its 18.7 million followers about a “GIVEAWAY ALERT.” For 12 days, a lucky winner would score a $500 online gift card by liking the post and tagging a friend, as well as “the lip shade you’ll be wearing the most this Christmas!”

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Then there are the YouTube hauls, the oddly viral videos of influencers showing off what they got for Christmas. In her 2017 haul that’s been watched 1.7 million times, Olivia Jade — a 19-year-old beauty and fashion tipster and the daughter of actress Lori Loughlin — sat on a plush white bed in polar bear pajamas and a Santa hat. One by one, she showed off a bottle of Valentino perfume (“sweet mixed with floral”), a cropped, purple fuzzy sweater from Urban Outfitters, bikinis, sneakers, jeans, underwear, high heels, dresses, tops and more. Oh, and an iPhone X. (The new camera means “better content for you guys!!!”)

It’s clickbait for a reason. Emilia Comrack, 15, has the Urban Outfitters Carmella Cozy Reversible Teddy Coat on her holiday list, similar to the one, she said, that’s been worn by YouTuber Emma Chamberlain. Emilia also spotted other YouTubers trying out Glossier’s Boy Brow, a tinted gel for shaping and filling eyebrows.

“If I see something I like on social media or YouTube,” Emilia said, “I’ll screenshot it or write it down so later on I can go back and look at the things I want to ask for.”

But Samuel Johnson said that after the holidays are over, all of the social-media hoopla leaves him uninspired. Samuel, 15, said he still does a lot of shopping online and draws inspiration from Instagram. But as he scrolls, he said, he has to get past images that “make themselves look perfect or show off what they have.”

On Christmas, he’s hoping for AirPods or Nike Air Force 1 shoes. But he said the targeted ads that Instagram uses to keep him hooked all feel kind of hollow in the end.

“People value shopping and gifts so much,” he said “they’re going to feel even worse afterward.”

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