Header and home page being cut off on the sides

[llennoxllc]

I was manually entering codes to solutions I found on other Shopify help forums. The goal was to enter codes that would expand my navigation bar to full width as well as give it a colored background. I achieved that but now my home page is too big and icons are being cut off. Can someone give me a solution to keep what I want to revert the sizing back to normal so that it doesn't go over the edge of the screen? See the image below. 

[llennoxllc]

I use the theme dawn. Under what file would I enter that code

[GemPages]

Hello @llennoxllc ,

Can you give me your Store URL( with pass if your store password is enabled) so I can check it for you?

Kind & Best regards,
GemPages Support Team

[llennoxllc]

I PM'd you