title: Underline all text in a row of an R dataframe
body: <p>I'm building a shiny app and I want to emphasize a summary row in some of my dataTable outputs. I would like all the values in the second to last row to be underlined. I'm not strong enough with HTML or CSS to know where to start with this. I've looked through a bunch of DT style guides but can't find anything helpful</p>