Highcharts JS theme

(qplot(hp, mpg, data = mtcars, geom = 'point')
+ scale_colour_hc()
+ ggtitle('Diamond Prices')
+ theme_hc())

## Use a Dark-Unica theme
(qplot(hp, mpg, data = mtcars, geom = 'point')
+ scale_colour_hc('darkunica')
+ ggtitle('Diamond Prices')
+ theme_hc(bgcolor = 'darkunica'))