Change Font Size on rCharts Sankey Diagram

I'm using the following code to create a Sankey Diagram using rCharts. I wish to increase the font size of the text printed on the Sankey Diagram. I can't find a manual to show me how to do this. Thoughts?

rm(list = ls())require(reshape)require(rCharts)require(rjson)target <- c('TMF', 'TMF', 'TMF','Evaporation','Mill Reclaim','Void Losses','Seepage')source <- c('Precipitation & Run Off','Slurry','Other','TMF','TMF','TMF','TMF')value <- c(638,1610,755,118,1430,466,2)x <- data.frame(target,source,value)sankeyPlot <- rCharts$new()sankeyPlot$set(data = x,nodeWidth = 10,nodePadding = 10,layout = 32,width = 1100,height = 675,units = "cubic metres",title = "Sankey Diagram")sankeyPlot$setLib('http://timelyportfolio.github.io/rCharts_d3_sankey')sankeyPlot