Is codepen causing the flicker or my shi$% code?

HTML-CSS
#1

Hey everyone,
I was wondering if there was something wrong with my code or if there was something wrong with codepen. My page seems to flicker on my iPhone 5s or and on my wife’s iPhone 6.It gets really hard to scroll down. I am wondering if it has anything to do with my JQuery code.

Thank you in advance !

#2

If you post a link to your pen, we might be able to help you figure it out.

#4