Find out error

Question

Thanks for tomorrow help.
But I struck with another error.
I modify the code.When user checked on checkbox then shadow will appear and then all the function work . But it not working. Please help me.
https://code.sololearn.com/W69SFRPlnx5g/?ref=app

Answer 1

Here's the corrected code:
https://code.sololearn.com/W3pclN5zekXU/?ref=app