Html section not highlighted

Question

I have created a section in html , in which I have shown some images and links , and I ran into a problem that in chrome developers tool that I found that section is not highlighted, that means the section is not present and elements are floating , and in the previous section I used float property with some elements , so is that problem ? What can do to fix this ?

Due to that I am not able to give the background colour as well .
you can view the last section in HTML whose class is : feature-download
and note this happens only when my screen size is less than 700 width as I have differentset of code for that
https://drive.google.com/drive/folders/1Q7bJvVlDHAaMPC_4s2-JKbpaAvGfVWmS?usp=sharing

Answer 1

If you link your program, someone on here should be able to spot your error quickly,

Answer 2

You can view the link of the project

Answer 3

Look for missing <>