Seating Availability Web Page

I want to create a seating availability program but I'm not sure how to approach the problem. I do not need it to require seat selection or actual ordering of the seats, I simply want to display how available each section is.

The seating plan should be partitioned into different sections but they will all be different shapes and must be able to update their colour to illustrate their availability.

There should be drop-down menus allowing you to select the show and the night of the show and the seating plan should update showing that night's availability; the different availabilities will be stored in a database.

I know how to create the database, the drop-downs, and update everything, but I do not know how I am going to design the seating graphic itself with all the different sections and have it able to update its colour.

What is the best/easiest way to do that? They can be shapes, there's no need for them to be built out of little seat boxes unless that makes it easier, although I would like to put the row letter beside the row.

I'm just looking for someone to let me know where to start, and the best tool to make the dynamic seating graphic split up into sections.

Thanks in advance!