meeting-room-booking-system/mrbs-code — reverse-engineered prompt

Build me a simple web based meeting room booking system like the old paper diary at reception, but online.

People should be able to open it in a browser, log in, see rooms grouped by area, check when each room is free, and book a meeting room for a date and time. An admin should be able to create the first admin account, add areas, add rooms inside those areas, and manage the setup. It should support normal database backed login, with room to configure other authentication later.

Please make it practical rather than fancy. Use PHP with a MySQL or PostgreSQL database, since this needs to run on a normal web server. Include the database tables and basic install instructions so someone can deploy it at a company. It would be nice if the look can be customized later to match company colors, maybe through themes or simple style files.

If you need current PHP or database docs, look them up online.