Caption font color with kable

Aha! Customizing the CSS stylesheet does the trick.

    caption {
      color: red;
      font-weight: bold;
      font-size: 1.0em;
    } 

Adding to Ani's answer: if you don't want to write the css stylesheet separately, you can just include another chunk after your YAML:

```{r results="asis"}
cat("
<style>
caption {
      color: red;
      font-weight: bold;
      font-size: 1.0em;
    }
</style>
")
```