Hello , I am new at Freelancer , But I have 5 years of experience to build websites, also WP sites.
I am checked your Sketch. It is very simple, and it is working well done in mobile devices also.
I am started now for the job, and finished ASAP (that means to 2 hours), and you will checeked the results to single reload on browser.
I am at front of my PC now ! And we will solve that ;)
Get in touch !