Menu site is not working on mobile

Hi,

I need some help with my site. I purchase Rhythm Theme https://themeforest.net/item/rhythm-responsive-multipurpose-theme-/11330434
and I have been working on it with my information and design https://www.lamissionporvida.org

My site is looking good on my computer but on mobile (responsive) my menu and images on my home cover are not right. I’m new with wordpress.

Any suggestion?

Thank you!