Refresh the page for different theme. The widgets are in two colors and multiple sizes available.

These keyboard shortcuts are available for active puzzle widget:
  - `d` for deleting last filled field.
  - `a` for auto resolving.
  - `u` for unlimited undo's.
  - `r` for a tip.

Developer notes:
 - Widget size is defined by font size on the .soduku css class or as html 
   attribute to the component.
 - You can use an existing puzzle by setting the puzzle attribute on a component. 
   It must contain at least 81 digits to be valid.