Hello,
I visited your website and I found different display problem.
For the project I should need:
1) url and credentials to the wordpress site.
2) Know if you will keep actual design page.
My plan is:
1) import new css, js.
2) control your actual script, css file and html structure, removing obsolete content.
3) modify your css and html.
4) rewrite website menu.
Schedule expectation: 14 days.
Regards.