Revamping the https://gp24.ro/ website

I am looking for help to revamp the https://gp24.ro/ website, with the goal of optimizing its front-end performance. The scope of this project is simplifying (theme) design, and we need it to be supported across both desktop and mobile platforms. Ultimately I'm looking for a modern look and feel that is responsive (90% = Mobile Traffic), making sure the website looks its best no matter the device. If you are up for the task, let's get to work bringing this project to life! As described in the attached file we have some plugins that we need to keep, others could be done otherwise.