Athleisure looks, outfits that combine athletic and leisure wear, marry style and comfort in a way that people will be wearing for a long time.

It started out as a slightly ironic trend: clothes meant for working out were instead worn for lounging around the house, taking notes in class and grabbing coffee with friends. Multipurpose outfits featuring sweats, sneakers and dressier jackets came into style because women needed one outfit that could take them through a busy and varied day in comfort and style.

A few years ago, exercise clothing stayed solely at the gym, but then leggings started popping up in street style photos, and sneakers began making appearances on runways. There are now seasonally changing trends in the activewear market instead of the timeless workout basics of years past.

While jean sales are on their way down, activewear sales are skyrocketing.

Stores are adding active styles and fitness lines to their offerings more every month. It was initially seen as a passing trend related to trendy normcore looks, but instead of fading away, the style has taken over the fashion scene and even trickled up into high fashion houses.

The tough part of mastering the athleisure look is making it look like fashion, not just straightforward gym wear. It’s not just exercise clothing — it’s dressed up exercise clothing.

The secret is to mix and balance sporty pieces with casual items. A pair of black performance leggings and Nike sneakers cover the athletic part, while a cropped ribbed turtleneck and leather jacket make the look acceptable to wear all day. The goal is not to look like you just came from the gym but like you might be going there later.

For inspiration, check out Rihanna’s sporty urban glam looks or Kendall Jenner and Gigi Hadid’s signature leggings/bomber jacket/crop top combos. Kendall and Gigi like to break the golden rule of leggings (keep your pelvis area covered) with their athleisure looks, but this fashion rebellion is actually acceptable because they choose performance leggings instead of thin cotton ones.

Performance fabrics that are thicker and opaque will smooth and cover well and are often designed with flattering seam designs, making them all right to wear by themselves.

Another trick is to stick to only one oversized piece to avoid looking unkempt. That item could be the loose track pants you wear with strappy heels and a clingy knit tank, or it could be the oversized jacket you pair with printed leggings and white sneakers. You can also combine sleek and sporty pieces to get a more fashion-forward athleisure look.

Doing a hoodie and joggers with a beaded top and high heels is creative and cool. Pairing some sporty kicks with a short dress or slipping a structured blazer or vest over a slouchy tee and leggings is unexpected and fun.

The best part is that athleisure is pretty much the answer to college students’ sartorial prayers. You know you wear leggings to class 90 percent of the time, anyway. Now you can easily tie a plaid shirt around your waist or throw a long coat on top and call it fashion.