Please need help in fixing bugs on my project

I just finished my Product page. Here are some bugs that needs fixing
my header links are not active including the link on the the subscription form on the bottom right. This same links become active when you scroll down a little towards the product section. please i have cracked my brains out for the cause of this strange behaviour.
2. it seems my media query have refused to work also. nothing changes even if i reduce the size of my browser. I could hug anybody that can help me solve these out. Don’t ignore please. Thanks in advance.
By the way, what is your rating on my work on the scale of 10. I want to know if I am really getting better.

link to project

@BookNowNow, I’ve given you feedback on your other pages and from what I can see that advice was never followed.
I’ll try again with this page.

Not sure if you’ve noticed but if you remove all the CSS your links work properly. That should be your first starting point. I’ll narrow it down for you. This is the line that’s causing your failure;

  • Run your HTML & CSS code through the W3C validator.
    • Each one has to be input separately, one at a time. Correct the issues with your HTML code and then your CSS code.

You’ll see why your media query isn’t working if you run your code through the validator.

I will do that and learn… thanks bro

If you don’t mind,can you explain why that line is the problem so I can better understand when to and when not to use it…

i have ran it on the validation and corrected all errors . please can you help me further on the links and why there are not working. I think I am having a general problem using position.

Some official documentation will explain a lot better than I can.