Website Design with Mobile Version - Please read detail below

General information for the website: Photography Studio
Description of requirements/features: I am the owner of Enchanted Photography - www.EnchantedPhotography.co.uk

In the past six months I have worked with several web designers on the above project to create the new website you will see at the above link. On a computer this website looks great but it has an incredibly poor performance on a mobile phone despite being 'responsive' with overlapping images, HUGE fonts etc.

The above site is created in HTML on Wordpress and is proving incredibly difficult to change photos and text at present. It has also been primarily built through 'posts' and not pages' to support the two tier navigation you will find on all pages beyond the landing page.

So I am looking for suggestions and proposals on how to fix this please. I know the site appears to have a huge number of pages however many are duplicates of the same design with just minor text or image tweaks. I am happy to discuss this further with you if you can find a solution to the above problem.
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