Level Numbers.

Why are the levels numbers different colours???

Have you ever wondered why the numbers for the levels 
are different colours?
Some are red, some are blue and some are green.
See pic.

The GREEN numbers are for normal levels. 
These are just run of the mill Solitaire with no timer or task.

The RED numbers are TIMED levels.
You have a given time to complete the level, 
AS WELL AS getting a high enough score.
To me the most difficult levels of all.

The BLUE levels have a task to complete. 
IE. Use the don't use the joker or use the gold card etc.
You will be informed at the start of the game
 what the task is.

These are examples of the tasks. 
There are several more