The mid-century modern style originated in America in the mid-1940s. The main wishes of people for the interior then were comfort and friendliness - they laid the main features of the direction: open, light space, simple and flowing forms, the use of natural wood, as well as bright colors and geometric patterns along with a muted palette.

The mid-century modern dominated interior design throughout the 1950s and 60s, and is now making a triumphant return - of course, in an updated version. Which one, see Virtual Staging Mid Century style here https://www.spotlessagency.com/portfolio/mid-century-modern-style-1
This style is characterized by the influence of organic forms, their simplicity, emphasis on functionality