Summary

Inspired by the Geometric Adjustable Laptop+ Stand by ConMacDesign (thanks!), this stand design is foldable, adjustable (4 positions 15°, 25°, 35° and 45°), portable (you can put it in your notebook bag) and, moreover, printable in one piece.

It takes 3 hours and 28 minutes on Original Prusa MINI+, standard quality.
No need for supports, raft or brim.
No need for screws or nuts, the stand is perfectly working once printed.

In order to have full stability you have to print 2 of them (see pictures).

Feel free to use the model as you want!