knitr - R Markdown - changing font size and font type in html output

Question

I am using R Markdown in RStudio and the knit HTML option to create HTML output. However, the font used in the ouput for plain text blocks is rather small and I would like to change it to a differnt font and increase the font size. Can someone show an example how to set the output font - workable without a lot of knowledge in html?

So far I tried at the top of my markdown document, but this doesn't work.

---
fontsize: 24pt
---

Answer 1

I think fontsize: command in YAML only works for LaTeX / pdf. Apart, in standard latex classes (article, book, and report) only three font sizes are accepted (10pt, 11pt, and 12pt).

Regarding appearance (different font types and colors), you can specify a theme:. See Appearance and Style.

I guess, what you are looking for is your own css. Make a file called style.css, save it in the same folder as your .Rmd and include it in the YAML header:

---
output:
  html_document:
    css: style.css
---

In the css-file you define your font-type and size:

/* Whole document: */
body{
  font-family: Helvetica;
  font-size: 16pt;
}
/* Headers */
h1,h2,h3,h4,h5,h6{
  font-size: 24pt;
}