Wow!
Very nice!
What are the techs of the website ? (It's a SPA ? Laravel? Others... ?)
php and notepad++
Take a look here:
https://laravel.com/And download Visual Studio Code (not the visual studio, only the VS Code), add laravel extension and what you think is needed.
I can help you config and run Laravel if you want, I did a L2J web panel and L2J Platform two years ago in Laravel, he is so nice!
Laravel is a PHP framework, I've used the v5.4 and v5.6, but his docs are great and I can learn fast the news to help you;
Use Laravel + Blade template (from Laravel), It is just a suggestion, I think this will make the dev more easy and code less for you