Hi,
I have read your project description completely and I am confident that I can help you finish up your website successfully for your needs.
I will fix your browser window resizes with custom CSS media queries, as well as menu and I might solve the wrong colors that way, too (or through theme options).
As for the wrongly formated pages, I will fix that with theme page builder or other custom page builder that you used in developing (I am familiar with Elementor, Beaver, Origin, UX builder, ...).
I will check for other errors as well, from invalid scripts, to design and page breaks and will lead you through the process so you are familiar with what I am doing at every moment.
Hope that the budget is okay for you and that I get a chance to work on, and finish your project succesfully!