Hi, i am highly skilled front end developer, and when it comes to responsiveness of a web page, i am the best shot you got, freelancer.com is full of scammers and unskilled developers, you can choose one of them but your money will go waste that way, i have reviews on freelancer.com but it's not my only work platform, i deal my clients locally and on social sites, i have recently built 3 web app projects from the same client from Germany, why i am telling you this? obvious, i want your trust, i have read your description and visited all the 8 links and i have checked your attachments also, in which you have given guidelines about the mobile view, i am a expert of CSS as i know everything about it, media queries, flexbox or CSS grids you just name it :), i am dividing the bid in 8 milestones, one milestone for one fully responsive page, the amount of money i have bidden for this project is more than it should be, but it feels good to work when you are getting a good pay off, but don't worry about the bid if you it's not a fair one, i will cooperate, and one last thing, you mentioned in description "this is far from easy" i disagree, and as for "2 freelancers have already tried" well those would be very unskilled front end developers then.
Thank you for your time,
Have a nice day,
NOTE : Feel free to contact me for any query (Even if am offline).