Widget Variations allow for the individual styling of each widget within a position, without it being global. Code wise, this is achieved by adding a class into the widget code which loads from the Widget Variations field in the widget settings. The theme CSS adjusts accordingly.
Choose any available variation at Appearance ??? Widgets ??? Widget ??? Widget Variations
There are 5 suffixes: high, med, low, noicon and flush.
High, Med and Low are linked to the standard styling of each body level. Therefore, you can make a module use the styling of the med body level when using the low or high body levels.
Noicon will disable the icon that is to the left of the module title (can be used in combination with others such as high noicon); with flush disabling module padding and margin for a tighter fit.