window knob child security

this is my version of a secured window handler to prevent child accident.
-secure code is modifiable easily when knob is disassembled
-there is an explain photo in files


need:
-glue,
-screws:
M3x12 (x3)
M3x35
-lighter spring (cut in 3x 7mm)
-M3 nut

Principe video:
https://www.youtube.com/watch?v=-yMkpPRyMrc

my daughter testing the system:
https://www.youtube.com/watch?v=4lF6FraS72o