article preview using HTML CSS jquery

my first challenge using JS...it is very much still incomplete but I am stuck. I think i need to go back and practice CSS responsiveness though because I really struggled here. My questions:

questions:

1. github pages is showing different CSS formating than when I copy full path directly from Atom...why?
2. can you include images, icons, or links in tippy? I tried a bunch of different ways, but it always ends up showing up as the full HTML text. even when using .text() not .innerHTML()
3. jQuery threw me for a loop here, I am brand new to it and gave it an attempt. What I want to happen, is when the button hover state is true, and the screen size less than 840px is true, then it runs a function that changes the layout (hiding the name and profile pic, and putting up a dark div, and includes social icons.