Last summer was all about pink. This summer, a shocking shade of lime green seems to have taken over. 

Blame Charli XCX. The singer released her now-ubiquitous album at the beginning of June with a simple cover: a solid green background with the word "brat" in a basic font. And whether you've listened or not, there's a good chance you've encountered brat culture in some capacity by now, from the "Apple" dance going viral on TikTok to brands using the iconic green to promote their own products.

On Etsy, shoppers and sellers alike have eagerly hopped on the trend.

Search Etsy for "brat" and you'll see over 1,000 results for brat-themed shirts, stickers, buttons, stationery and more. Some directly reference the album's lyrics and themes, like "365 party girl" or "so Julia." Others pair the brat green with different cultural phenomena like Taylor Swift lyrics, or increasingly, homages to Vice President Kamala Harris.

DON'T MISS: Achieve Financial Wellness: Be Happier, Wealthier & More Financially Secure 

Etsy confirms shoppers are on the hunt to get their brat on. Searches on the site for "brat" were up 35% over the last three months compared with the previous year, and searches for "lime green" are up 40%, the company told CNBC Make It in an email.

For the politician's part, Harris's social media team changed the banner on her campaign's X profile to a brat-inspired image of her name against the now-iconic green shortly after President Joe Biden announced he would not be running again and endorsed Harris for the Democratic nomination. Charli XCX herself even posted "Kamala IS brat," seemingly endorsing the candidate.

Here's how Etsy sellers are getting in on the action.

Where pop meets politics

Ashley Yang started selling brat-themed shirts on her Etsy store, DeepCutsUSA, in June, soon after the album was released.

"[The album] was something that I was really enjoying and listening to and it was the line, 'I'm so Julia' that I was like, 'you know, I think people could personalize that, right?'" Yang tells CNBC Make It.

Soon after listing customizable lime green shirts on her store, Yang added shirts that already said "brat," including in toddler sizes. As a mom of two herself, she loves "seeing parents being able to participate [in the trend] with their kids."

"It's really cute," she adds.

Harris's brat endorsement kicked sales up a notch, she says. The seller brought in $1,014 in June between her brat-themed items and custom Beyoncé-inspired "Cowboy Carter" sashes. Her revenue jumped to $2,422 during July, with a significant uptick after Biden's departure announcement and Harris endorsement on July 21.

In addition to shirts, Yang sells a brat flag that also picked up steam, becoming one of her top-selling items. Yang's brat-themed products alone have brought in over $1,200 since she listed her first lime green shirt on June 22, according to documents reviewed by CNBC Make It.

Other sellers have benefitted from the brat zeitgeist and accompanying Harris effect, too.

"I think we've sold a couple hundred of those things just for the last few days," Brenna McCaffrey tells CNBC Make It of her Etsy shop's brat-themed items. 

McCaffrey and her sister, Devon, have run the shop AugustandArcher for a little over a year. They started selling lime green shirts and stickers inspired by the album and the internet's explosive reaction to it just after Biden's announcement. 

Their brat-themed, Harris-inspired merchandise quickly became bestsellers after the news. The sister duo has brought in $545 in revenue from their $9 brat/Harris-themed bumper sticker since listing it on their store on July 22, according to documents reviewed by CNBC Make It.

"Brat" was the perfect inspiration for McCaffrey who says their store is all about "celebrating the things that we all enjoy together, whether it's a song or a movie or just a vibe, and making it [into] something really fun and personal."

Want to stop worrying about money? Sign up for CNBC's new online course Achieve Financial Wellness: Be Happier, Wealthier & More Financially Secure. We'll teach you the psychology of money, how to manage your stress and create healthy habits, and simple ways to boost your savings, get out of debt and invest for the future. Start today and use code EARLYBIRD for an introductory discount of 30% off through September 2, 2024.

Plus, sign up for CNBC Make It's newsletter to get tips and tricks for success at work, with money and in life.