First let's say "Happy Birthday" to our birthday girl Selena Gomez who celebrated her 24th one on July 22, although we all know every night is her birthday. (Don't get it? Go listen to her song 'Birthday'.)

Having the most followers (90M+) on Instagram, Selena is not only in the singing and acting field, but walks on the edge of fashion. Over the years, she has successfully transformed from the childish Disney girl to an edgy and mature celebrity. Certainly she has updated her wardrobe and hired a bunch of new stylists.

Fabulous Victoria's Secret angels cooperated with Selena to shoot another special lip sync version of her song 'Hands to Myself'.

Many fashion magazines, such as Elle and Vogue, have written about her. In fact, she's just got the cover on the June Issue of Vogue Brazil, with Nicolas Ghesquière, creative director of Louis Vuitton.

Red Carpet

Selena has a tendency to wear mono-color dresses. To some people, her one color simplicity might not make the best dress on the carpet. However, less is more. As simple as the dress defines in color, shape, fabric, etc., Selena dresses this way to amplify her own glamour.

This silver Galvan slipdress is extremely simple, yet the color matches her tanned skin perfectly. With the classic "leg pose" taken from Angelina Jolie, she was definitely a hit of the exhibit that night.

This dark blue shining dress from Calvin Klein Collection at the Grammys greatly strengthens her body shape, no wonder later that night the dress was melted by her hotness, leaving "bruises" on her hands.

Sorry, Selena! It's not you, it's the dress.

Black dresses are many women's all time favorite. Besides the color, the design is also divine. the mesmerizing lace did well extending her neck and showing a bit of the breasts, while lower down the combination of long and short dresses made the legs look slender. The accessories were also a good match: the shoes, bracelet and clutch are all in gold, which also matched the black dress.

The image was shot this year, so she's up to date with this year's fashion trend! Dressed in an off-shoulder pleated gown and matched with a box clutch, she looked just like a goddess from ancient Greek myth. I'll give a nine for this one!

The gown and accessories are good, still like a goddess. The hair? Not that perfect though.

This year, her Met Gala carpet look is pretty casual, but it looks as good as the formal ones. The black leather bra and boots are incredible. Plus, her makeup made she look stunning.

This is from 2014 Met Gala. The Diane von Furstenburg dress is still simple and classic. Again, I really like the earrings. Well, the makeups and the hair are not that good however.

Another red one, another Calvin Klein Collection.

For the record, Selena isn't always about one-color dresses though. Some of her patterned dresses also made her radiant.

The last one is a bit casual, but the color is fierce -- and after all, I find her like Louboutin and Jimmy Choo shoes a lot, just like other celebrities.

Street Style

Of course, the wardrobe transformation isn't only about red carpet but daily wear. Although she's not enough to be called "IT" girl like Kendall or Gigi, Selena is dressed stylishly in her own way.

Let's start with this one. Just like her red carpet looks, when it comes to daily clothing, she still prefers minimalism in fashion, especially black and white, sometimes grey. Why? Because basic clothes never go wrong!

Notice the sunglasses? They're one of her chicest accessories! With the suitable and in-style ones, you'll immediately become more fashionable.

This red sporty outfit from Vetements are perfect on her! She rocks the athletic outfits as well as Kendall and Gigi do.

This one is from Paris. The wide-brim hat and silver handbag really made the whole look simple and chic.

Up to date with this year's PJ trend! The lip color matches the shoe color.

True effortless chic! The items included in this look are basic, but they match each other; and again, the perfect sunglasses.

The white print dress here is also an "easy fashion" item! Put it on and you won't have to wear T-shirts or jeans.

In order to look good, white clothes can have additional requirements than dark color ones, but Selena killed this one. She's tanned and slender enough to be fabulous in this white look. Plus, her shoes have earned her extra scores.

Another white look to end the passage! I have to say, she's really good at accessories! The platforms, the handbag and the belt really make the outfit descent and sophisticated. Besides, the lip color is also epic.

The complete 24 looks are here! Let's keep our eyes on her and discover more. She has a reason for owning the most followers on Instagram.