getBlockVariation = function(blockTheme, blockVariation) {
            if( $.isArray(blockTheme) ) {
              if( blockVariation !== null && typeof blockTheme[blockVariation] !== 'undefined' ) {
                return blockTheme[blockVariation];
              } 
              else if(blockTheme.length > 0) {
                return blockTheme[0];
              } else {
                return null;
              }
            } else {
              return blockTheme;
            }
          }
The theme allows us to do many things:
- Use a specific color for the falling block (primary), regardless of the proper color.
- Use another color for the placed blocks (secondary).
- Default to the "original" block color in any of those cases by setting primary and/or secondary to null.
- With primary and secondary as null, all blocks keep their original colors.