Product Landing Page navigation bar overflow

Tell us what’s happening:
‘’'I have just started creating my product landing page. But my content overflows into the navigation bar as I scroll down. Can someone tell me how to fix this problem. Also, I know my code is not good.So,suggestions will be helpful.

Your code so far
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User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.88 Safari/537.36.

Challenge: Build a Product Landing Page

Link to the challenge: