Mobile First Approach (FLEXBOX + MEDIA QUERY)

Was doing the mobile first design and it was looking easy. Javascript was also easy to apply here. But when I came for the desktop design then I realized it is more complex in styling. I wanted to keep the functioning of the components same as I did for mobile design. So I had to use positioning(relative / absolute) to move the div containing share-links. I didn't know if it is a good approach or I could have done it in a better way. But I managed to do it in the end without altering my js file. So If anybody can take a look at the code and can give suggestion to improve efficiency in such type of design I will be thankful.