Build a bridge using your mouse and available budget. When it is done click "Test your bridge". 
Your workers will use it to get items located at the other side of valley, and bring them back to the shop. Your goal is to collect all items in level.

For each level you have limited budget. All money that you won't use, become your score, so cheaper bridge = higher score. 
Money collected in all levels of game will be your total score and will be sent to leader board. You will use those money in challenge mode too.

Building tips:
* There are two types of bridge elemets: "walk" - workers can step on them, "connectors" - used only to connect elemets of the bridge, workers do not collide with them.
* "Connector" elements are cheaper and lighter so use them as much as you can
* Each type of item have different weight and some of them will need stronger bridge then others.
* At the begining of game only wood elements of bridge are available. In further levels, aditional materials will be accessible also, so use them wisely.