How To Play
Use the arrow keys to guide the falling blocks, spacebar and the up-arrow will rotate the block in opposite directions.
Alternatively the keys A,W,S and D can be used as arrow keys for the same purpose.
When a complete horizontal ring of 15 blocks is occupied by pieces the row will collapse and earn you a point.
If four rows are cleared at one time you will be awarded an extra bonus point.
Visibility
If you are having trouble discerning the blocks in the game make sure the widget is displayed against a plain background.
Also try setting the block type to 'Wafer' or enabling ghosts in the Settings menu.