New York CNN  — 

The team at Pinterest felt it had to go dark to do right by its users.

At a time when social networks are plagued by toxic content, misinformation and partisan bickering, Pinterest (PINS) has arguably been one of the few feel-good social sites around. According to the company, people often turn to the digital scrapbooking service before bed, looking to calm themselves with Pinterest (PINS)’s endless trove of design, food and travel pictures.

But Sha Sha Chu, an engineer working on Pinterest’s Android app, thought the company could make the service even calmer, especially in these late-night moments, by investing in dark mode. This increasingly popular feature flips the default white background found in smartphone apps to black and gray.

“While many apps are moving toward a dark mode option, we felt especially responsible for offering dark mode because people often come to Pinterest for calm and relaxation, and turning down brightness can help,” Chu told CNN Business.

Pinterest officially introduced the dark mode option in late September, joining a design trend that has swept across many of the most popular apps throughout 2019. While some version of this option has been around for years – early computer terminals even offered green text on black backgrounds – Apple (AAPL) helped kick off a wave of renewed interest in it by bringing the feature to iPhones this year. Instagram and Gmail have also rolled out dark mode options and Facebook (FB) brought dark mode to desktop users.

For Silicon Valley, the shift to dark mode – however minor it might seem – is part of a broader push to improve the health and user experience of their platforms at a time when tech companies are under scrutiny for their impact on our politics and personal well-being.

“Right now, Silicon Valley wants to be seen as promoting human happiness and well-being, not downgrading our capabilities,” said Andrew Hogan, a principal analyst at Forrester.

In addition to being a calmer experience, dark mode is often thought to be easier on the eyes and potentially does less to disrupt your sleep than staring at a bright phone late at night. The option also “makes it easier to stay focused on your work,” according an Apple support page.

And it’s better for your battery life too. This is because darker pixels require less power than lighter ones. On some displays, dark pixels require no power at all. A Google (GOOGL) study found power savings can be up to 60% with dark mode on Google (GOOGL) apps.

Many prominent tech platforms introduced dark mode options this year as part of a broader industry push to show they can improve the well-being of their users.

Although going dark may seem as easy as flipping a switch, the companies say designing this feature requires fixating on some painstakingly minute details.

“There were multiple layers to implementing dark theme,” Shenaz Zack Mistry, Group Product Manager at Google, told CNN Business. “It was a massive effort across many teams for over a year.”

Designers on Google’s Android team had to meticulously assess how to convert the light theme experience into the dark theme, addressing issues such as color contrast Likewise, the Facebook Messenger team, had to choose what shade of black to use – and then a specific color had to be picked for every aspect of the screen, including the green active status dot.

“If we just reversed the colors, it’d be glaring and punctuated,” said Loredana Crisan, product design director for Facebook Messenger.

Those efforts appeared to pay off. Users have flocked to the dark side.

Dark mode “has been one of the highest requested features from our users,” Mistry said. In September, Google rolled out dark mode to Android 10. It didn’t release exact numbers, but Mistry said “a large percentage of Pixel users” have already adopted the feature.

According to Forrester’s Hogan, dark mode has taken off at least partially due to users’ desire to differentiate themselves. Hogan described the feature, which users have to know to enable on an app or website, as “cool, novel and new.” In this sense, it is similar to other ways users can customize their apps and devices to differentiate themselves.

However, it’s unclear whether dark mode is actually easier on the eyes, according to Christopher Starr, an ophthalmologist at Weill Cornell Medicine. It largely boils down to personal preference as there are many variables – such as ambient room light and angle of the screen – that can affect eye comfort when staring at computers and devices.

“Ultimately eye strain and computer vision syndrome is more about the amount of screen time without breaks and the reduced blink rate we see with digital device use,” Starr said.

Still, Hogan believes this is only the beginning of the trend of features addressing the downsides of screen time.

“Five years from now, we’ll probably be staring at more screens,” Hogan said. That means we’ll also likely still be trying to find ways to reduce the harmful impacts. But he said it’s unclear whether the dark mode feature, in particular, will retain its “cool factor” or if people will have moved on to the next fad.