This is the source for the online betting game under https://friends-of-simulation.org that was organized for the FIFA World Cup 2018. It consists of PHP + Javascript code using jquery as well as stylesheets (css), images and a mysql database. The database without user data (but nations and matches) can be created by the sql code provided in empty_db.sql.
A mysql database and a php webserver is needed. The database credentials need to be adjusted in connect.php.
If you want to use the code, please read through the whole code at first. At some points there are commented-out sections or extra code that was in use at some time during the tournament. Also some parts are specific to the World Cup 2018, e.g. the automatic match result assignments.