Problems to modify the information window.

Hello friends of the forum,

I’m new and I’m starting to work with OSM.
I’m working with MySQL and PHP, so good my queries data points shows me on the map. But when I click on the point I get a sale and the information that comes from my database, I want to modify the information window … How I can do that?, Giving size, color, etc …

Thank you very much friends, I hope your answer.

This is my code…