What kind of feature is the "hidden" detail that often appears in Moia's clothing descriptions?

The concealed features at Moia are mainly found in the side seams or inside the hems. It is a recurring method across various garments, to the extent that the word "hidden" was used in the descriptions of 33 items out of the 241 examined^[1].

They alter the shape from the inside without increasing externally visible details. For items like the washed stripe shirt or the stripe shirt, fastening the button concealed inside the side seam creates an asymmetrical silhouette, or unfastening the button allows it to be worn arranged in a basic silhouette^[2][3].

A similar feature is also incorporated into the hem. The half placket shirt is designed so that pulling the string hidden inside the hem adjusts the circumference and silhouette^[4]. Throughout the clothing, features are provided that allow the wearer to directly change the silhouette without exposing buttons or strings on the outside.